Snake Game

Hi there! I'm currently working on a Snake Game project for a passion project for my brother who has autism. However, I'm not sure how to execute the code. I already have a bit of the structure written out but need help completing it, and I was hoping you can do that for me! I have attached the flowchart and what I currently have for the code with this message so you can see if this is something you can do. I was wondering if this can be done with only simple code? So only Input/Output, Variables, Data Types, Conditionals, Methods, Strings, Loops, Arrays, Files, Classes & Objects, and ArrayLists? Additionally, is it possible to do the project on IntelliJ? As it is the program I am currently using for this project. Let me know!