I found a img.sheilds logo of python using this,
https://img.shields.io/badge/-Python-black?logo=Python&style=social
How can I get C++ logo ?
Just replace Python with c++. And as + is a special char in the query part of the url it has to be encoded as %2B:
https://img.shields.io/badge/-c++-black?logo=c%2B%2B&style=social