First of all you should determine if you want to learn hand lettering or calligraphy.

These two terms are used interchangeably all over the internet but hand lettering and calligraphy are two very different things. Check out this article that will explain the difference between the two.

If you are more interested hand lettering, drawing and illustrating the shapes of the letters, then you should start off by reading this article.

In case you want to learn more about calligraphy and the art of beautiful writing then you can start off with this article

The best way to get you started (regardless from your choice) is to start off by learning the fundamentals and to build your knowledge and skills from there. If you are a total beginner start with basic shapes, single letters and words, avoid jumping right on creating long quotes with complicated layouts and a bunch of different effects (like shades or 3D). Focus on the basics, and as you move forward you will start to expand your skills and knowledge.