I just wanted to recommend Leslie Sansone's Walk At Home. It's very simple, lots of workouts on you tube, you can do it at your own level , and is surprisingly effective if you do the more intense workouts. You do need some space but not masses - you could do it in most living rooms if you pushed back coffee tables etc.
I came across it when I was losing weight a few years ago. There are lots of online exercise programmes but something about the simplicity of this one really worked for me. Some people find her annoying but I quite like her breezy enthusiasm.
Once you get the hang of it, you can have the workout on your phone and be watching TV at the same time, which makes longer workouts less boring.
Just posting as I wait to find out if I'm confined to the house from Monday ...