Build your main character:
For this you will need to make 16 animations.
An animation of your character walking North, South, East West, North East etc.
You will also need an animation of the character standing still facing all direction.
May I recommend that you keep it simple. A general template so that you can easily make variations for new characters. For example, a hat wearing one. One with wings. One with a beard....
If you want to make your life easier. Don't use diagonal directions. This halves your workload.
Get the size right from the start. Use something like Photoshop to make a demo picture of how big you want the character to be on the screen against a background.
This is an interesting project.... Good Luck!