It’s a calculus thing. We can only give the expression a value if we know the functions giving us a zero value that are being devided. For example if we were dividing the function (X) by the function (X^2) at zero our we would get infinity (Wikipedia has a pretty good page on indeterminate forms).

You could also think of it like multiplying both the numerator and denominator of a fraction by 0. This should preserve the fractions value, but multiplying by 0 essentially erases both values so we can no longer know what the fraction equals unless we know how both values came to be 0.

0/0 is an indeterminate form and could equal anything depending on the specific zeros Involved.

It’s not nearly as hard as it seems, but you do have to be willing to search around Google for a bit and things might take a few tries to get working. Steam has an option in their compatibility settings to run windows games through Proton that has worked well for me, but I only really play smaller single player games. Can’t vouch for how well it works for multi-player stuff. Also I’m using Manjaro (based on Arch Linux) not sure if it works the same for all distributions.