Wayback Save is simple command-line utility save URLs to the Wayback Machine.
Wayback Save requires Python 3, Selenium for Python 3, and geckodriver.
On macOS, these can be installed easily with Homebrew using the following commands:
brew install python3 geckodriver
pip3 install selenium
The usage is simply:
wayback-save URL [URL...]
This script is very slow and is only practical for a very small number of web pages. If you wish to archive full websites then Archive Team's ArchiveBot is a more practical solution for you. It can crawl websites with up to a few hundred thousand urls.