configure: error: libmpfr not found or uses a different ABI (including static vs shared)

Heyo all, I've recently been working on a small side project regarding a custom Linux distro, not with the LFS instructions. Currently, I'm compiling a cross-compiler for gcc. Anyways, I get this error when I make:

configure: error: libmpfr not found or uses a different ABI (including static vs shared).
Makefile:5730: recipe for target 'configure-mpc' failed
make: *** [configure-mpc] Error 1

UPDATE: I installed mpfr via apt on that machine, which now gives me a slightly different error:

checking for recent MPFR... no
configure: error: MPFR version >= 4.1.0 required
Makefile:5730: recipe for target 'configure-mpc' failed
make: *** [configure-mpc] Error 1
handy/install: line 276: x86_64-unknown-linux-gnu-gcc: command not found

Strange thing is, the mpfr tarball that it should be using is 4.1.0... I don't think the apt package is >= 4.1.0, and not sure how to throw it up to 4.1.0. You can find my script [here](https://github.com/semissioncontrol/semcOS/blob/development/handy/install) , Static GCC starts at [Line 239](https://github.com/semissioncontrol/semcOS/blob/development/handy/install#L239) . I've done some research, but can't seem to find much. I *was* able to find someone mention that switching distros worked, and then that it was their MPFR version that wasn't working. This one is compiling on Ubuntu WSL @ Windows because my laptop is faster - if needed, I'll be compiling this on my PC @ Gentoo soon. My MPFR version is 4.1.0, GCC version 10.2.0. Why is this happening? Cheers, Bobbbay