Query about local folder in root/usr

Okay,I dont know much about terminal. Actually Whenever I try to download something by taking help from internet, they expect it to get downloaded in usr/local/bin folder . But as my local folder is empty, it contains no bin folder (for eg I downloaded gcc using homebrew by "brew install gcc" , but not able to use it)

Okay, like initially when I ran "where gcc" it gave "usr/bin/gcc" , this one is preinstalled . But when I ran "brew install gcc", command "where gcc " still gave the same result "usr/bin/gcc" . But I expected it to print 1 more path where brew installed it

Also, many of my friends contain bin,include etc folders in that local folders (but they use intel mac), that's I want to clarify.