After you finish compiling and installing each item, you need to return to /home/tc before downloading the next item.
Download mpfr-4.0.2.tar.xz, gmp-6.1.2.tar.xz and mpc-1.1.0.tar.gz in the same way as you downloaded binutils-2.33.1.tar.xz and gcc-9.2.0.tar.xz