To install Python 2 on Ubuntu 20.04:
$ sudo apt install python
or
$ sudo apt install python2
python-pip may be no exists anymore in 20.04, and looks like it has been removed from the repositorie.
To install pip for Python :
$ curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
$ sudo python2 get-pip.py
$ sudo python2 get-pip.py
If you run "python2 get-pip.py" without sudo, you have to set PATH after installed.