Image copyright Andrei Lussmann Image caption Andrei Lussmann owns a chain of six restaurants across the south of England

"A restaurant kitchen is completely different from a production kitchen, and we had never delivered a unit of food," Andrei Lussmann says.

His firm now completes about 400 online orders in one weekend.

Andrei is just one business owner who has totally upended operations because of the coronavirus lockdown. He owns a chain of six restaurants, focusing on food from sustainable sources.

The pandemic hit Lussmanns hard. The week before the closure of restaurants and pubs was announced by the government, it had opened its latest outpost in Oxford.

"It became very clear that we should close sooner rather than later," he says. "But because we have a slightly older generation that eat with us, we thought we should do very good food that can be delivered to the door."

The majority of its wait staff were furloughed and one of the six restaurants became a "dark kitchen", producing boxes of food for local delivery that include organic ready meals and pantry items.

After 30 years of running a restaurant company, Andrei had to turn the business into an e-commerce site within 30 hours.

Stark choices

The hospitality industry has been one of the hardest hit by lockdown measures as consumers stay away from pubs, restaurants and cafes.

But after the initial shock of the sweeping shutdown, and the realisation any return to normal could be months off, some firms are facing up to a stark choice: adapt or face the consequences.

Well-known chains such as KFC and Burger King have opted for the former, reopening some restaurants with a pared-back menu for delivery only.

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Both fast-food firms have said that fewer staff will be working in the kitchen as a result, and should be able to observe social distancing measures - keeping at least 2m apart from each other.

Burger King's workers will wear masks and gloves and be trained in running delivery-only kitchens hygienically.

Sandwich chain Pret a Manger has done something similar, reopening just 10 restaurants near London hospitals.

Chief executive Pano Christou told the BBC's Today programme that its shops will only offer takeaway or delivery, manned by staff who have volunteered to come back.

One worker will be allowed in a certain area of the store, such as the fridge or break room, at a time.

'Matter of survival'

While many restaurants have pivoted to online in order to survive, some fashion chains have had to do the same.

Next, which makes more than half of its sales online, has warned it faces a "very significant drop in sales".

The retailer stopped taking orders on 26 March and closed its High Street stores on 23 March - one day before lockdown came into place.

After a three-week break, the firm started selling some items online including children's clothes, after improving social distancing measures at its warehouses.

Image caption High Street retailer Next has capped the number of online orders it accepts day-to-day

Once a certain number of orders has been placed, the website now becomes "browse-only", to ensure those workers can cope.

As the High Street remains in shutdown, other retailers such as Topshop have opted to cancel orders with their suppliers to free up cash.

New Look also recently informed its suppliers that payment for stock already sitting in its shops or distribution centre would be delayed "indefinitely". It told manufacturers that it was "a matter of survival".

As Lord Wolfson, the boss of Next, said: "People do not buy a new outfit to stay at home."

Empty seats

Struggling airlines are also looking at how to adapt their services in anticipation of social distancing rules remaining in place until a vaccine is found - thought to be a year to 18 months away.

EasyJet has said it is considering keeping the middle seat on its planes empty when it resumes flights. London-based Wizz Air has floated the idea of providing protective gear for passengers.

However, the crisis hasn't deterred one small travel firm.

Travel Curious, a London-based tour company, was set up just 12 months ago. But as travel came to a standstill, it decided to ask its guides to run live virtual tours on Instagram.

Where governments are allowing people to walk in cities, walking tours are filmed by a family member already sharing a household with the guide.

Other tours are hosted from home, where restrictions on movement are more strict. One Venice "excursion" recently took place from a tour guide's apartment that overlooks the Grand Canal. Viewers are then asked to give a tip at the end of the tour.

Amir Azulay, chief executive of Travel Curious, said: "Watching a live-streamed tour on Instagram is not quite the same as actually being there on your own, but it's the next best thing.

"We wanted to support our tour guides at this time, and to provide some welcome respite for people by bringing the world into their homes."

Keeping up with customers

Supermarkets have also been forced to make big changes, although for another reason entirely - to keep up with soaring demand and ensure the safety of shoppers and staff.

Tesco boss Dave Lewis, for example, wrote to customers saying staff will draw new floor markings in the checkout areas, install protective screens on checkouts and introduce one-way aisles.

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Meanwhile, Waitrose is limiting the number of customers in its stores at any one time, with "marshals" enforcing social distancing rules.

Most UK supermarkets are prioritising deliveries for vulnerable and elderly shoppers during lockdown too.

This has been a sticking point for many people who, despite following Prime Minister Boris Johnson's request to stay at home and use online deliveries, find themselves unable to book slots.

Asda and Tesco have added hundreds of thousands of delivery slots, while Morrisons has partnered with Deliveroo to offer a 30-minute delivery service from 130 of its stores, with up to 70 products available.

And while boosting his firm's online presence has been a success so far, restaurant owner Andrei does have some worries about what happens next.

"We have no idea what things will look like on the other side," he says.

"If government restrictions are lifted, the general public won't come bouncing back into restaurants, and the whole point of hospitality is there's a personality, a handshake, a smile."