what are the steps to make a chess game in unreal 4?
Use the Chess Game Creator asset available in the unreal engine marketplace
First thing first, I recommend you get familiar with the minimax algorithm. You can find many tutorials on the web about it; my favorite is the one at geektheory: Minimax Algorithm in Game Theory | Set 1 (Introduction) - GeeksforGeeks
For more insight on how to write your backend, poking thorugh Chessprogramming wiki is also quite valuable.
And maybe do not start with chess, but something easier – for example, you might try a game of tic-tac-toe with a 8x8 board. It’ll help get you familiar with the above mentioned minimax, and other techniques you’d then re-use for your chess game (for example, the way you’ll decide to abstract and represent your board – Board Representation - Chessprogramming wiki)
All of that can be made with minimal graphics; you don’t want to spend your time onto that until you do have a solid backend. Once you have it, you can go nuts with representations. Oh if I miss Battle Chess 
Hope that helps!
Cheers
f