How to start using Unity to make a 2D mobile games?

Hello everyone, I know my question pretty basic but somehow I didn’t find the answer I wanted on the google. Here’s the details.

I’m graphic designer, a 2D graphic designer, I use Adobe Illustrator to create graphic so my graphic is mainly in vector form. I recently took interest in building a 2D game for mobile devices iOS/Android. The game I want to build is a platform game. So my question is how do I start up? I have totally zero experiences in building game and never use unity before, I also never build graphic for games, the only skill I have is to create 2D graphic but I don’t really know what graphic should I create and how it should be created by layer or just one big photo etc. So in my condition how do I start up building a 2D mobile game using Unity?

Thanks

Hardest part will be learning how to program. As for beginners, best way would be probably checking out unity tutorials on youtube.
https://www.youtube.com/results?search_query=unity+2d+tutorials

A suggestions, don’t use ready written code, you will never learn like that,
do everything yourself.