I linked gcc using homebrew, however, cannot find gcc

I linked gcc using Homebrew, however, what I can see are gcc-9 and g++-9. I cannot see gcc and g++.

Before I link them, I had a gcc and g++ in the path of /usr/bin, however, there version is 4.2.1. So to update gcc, using brew, I linked gcc and the path where I linked is /usr/local/bin.

I am using mac.

what is my problem? I need to use latest version of gcc, however, I cannot find gcc where I linked gcc using homebrew.