Xavier, there’s a doctrine grid that a website called CARM created that shows what are the primary and secondary essentials, everything after that breaks down into non-essentials. The website tends to be very conservative in theology, but the grid is smack dab on the money because it points out the essentials which is what form the crux of Christianity and it’s quite simple. You can check that out here: https://carm.org/doctrine-grid.

Denial of those essential beliefs would mean you couldn’t claim to be a Christian.