1# install flask (basic, if path is not set yet)
2py -m pip install flask
3# or set PATH to use pip:
4setx PATH "%PATH%;C:\<path\to\python\directory\>\Scripts"
5pip install flask
6# if "connection error: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed" [!]:
7py -m pip install --trusted-host pypi.python.org pip flask
8# if PermissionError: [WinError 5] Access is denied
9py -m pip install --user flask
10# or via creating a virtual environment venv:
11py -m venv c:\path\to\new\environment
12# then execute:
13c:\path\to\new\environment\Scripts\activate.bat
1pip install flask
2Or If The Problem is "pip" not Found Use :
3py -m pip install flask