How to go back to default GCC version of Ubuntu 18.04?

$ gcc --version
gcc (Ubuntu 10.1.0-2ubuntu1~18.04) 10.1.0


$ type -a gcc
gcc is /usr/bin/gcc


$ update-alternatives --query gcc
Name: gcc
Link: /usr/bin/gcc
Slaves:
 g++ /usr/bin/g++
Status: auto
Best: /usr/bin/gcc-10
Value: /usr/bin/gcc-10

Alternative: /usr/bin/gcc-10
Priority: 60
Slaves:
 g++ /usr/bin/g++-10

I don’t exactly remember what steps I followed to get to this version.

I want to uninstall the new gcc and have just the old one back.
Please help me to revert back to default version on Ubuntu 18.04.