Enter to rename rather than open is one of the dumbest UX decisions ever made in a file manager. And then doubling down by not allowing any key remaps at all so you're stuck with it.
Oh, then you were probably not pissed enough to search more thoroughly. :) Fortunately, there's a godsend man who wrote a utility called 'PresButan' - https://briankendall.net/presButan/index.htm . Doesn't always auto launch with the OS start for some reason, but works great when it's running and fixes this madness.