Future Learn – A collection of free on-line courses, many from universities.
There are two more sites like this:
Board Games. Here is a really good site for playing board games. You don’t play against the computer, you play against each other. One person needs to join (Free – and remarkably few details required) and choose a game. Once they have done that they can invite other players by e-mail. Tabletopia
Bridge: a useful link if you want to investigate how to play Bridge https://www.nofearbridge.co.uk/U3A/