Open a CMD windows and run the following:
gh repo clone protocolbuffers/protobuf
cd protobuf
git checkout v3.5.2
cd cmake
mkdir build
cd build
mkdir solution
cd solution
cmake -G "Visual Studio 16 2019" -Dprotobuf_MSVC_STATIC_RUNTIME=OFF -Dprotobuf_BUILD_TESTS=OFF ..\..
cmake --build . --config Release --target protoc