Hi there! As a general guide to new creators, we recommend reading https://www.chess.com/clubs/forum/view/custom-variants-club-directory as it contains many helpful guides to variant creation!
Additionally, if you want feedback for your variants, I recommend you post your ideas at https://www.chess.com/clubs/forum/view/new-position-workshop-testing-thread
I have an Idea for a new chess varient, duck pond chess. the board size is 8x8, on ranks 4 & 5 16 ducks are passed, if a player is stalemated they loose and a player may move a duck each turn. other than that it is normal chess.