You could just go to the Help menu and then look into the tutorials.
Or go here: https://www.adobe.com/de/learn/illustrator?locale=de&learnIn=1
And then you should take a look at a tutorial that guides you through the interface so you know how to handle all the tools and panels. Afterwards check out what's on the page and what you want to create.
What you need most will be basic shapes and the pen tool:
https://www.adobe.com/africa/learn/illustrator/web/shapes-basics?locale=en-x-AFRICA&learnIn=1
The pen tool requires practice. So if it doesn't work at first: that's not your fault. You just have to keep doing it. It's like eating with fork and knife: first you don't know how to hold it, then it becomes second nature.
Then you also need to know how to combine shapes. That will be the job of the pathfinder panel and/or the shapebuilder tool or Live paint. Apart from that you will need to know how to set up the file for production, but I would just start with creating something.