Issue with downloading Makerom and completing the CIA

[ch14seedlol]

When I got to the part of downloading the Makerom code, it gave me this error.

ERROR: The certificate of ‘github.com’ is not trusted.
ERROR: The certificate of ‘github.com’ doesn't have a known issuer.

I didn't have problems with running any other code, just that one. But I simply just skipped it to see if I could still finish this without installing the Makerom. Making the 3dsx file was fine but when I ran the code to make the CIA file at the very end when it was done running the code I got this error.

/bin/sh: line 1: makerom: command not found
make: *** [Makefile:934: build/us_3ds/sm64.us.f3dex2e.cia] Error 127

I don't expect to get an immediate response but I wanna know what can I do to download the Makerom without getting an error.

Thank you.