For people who only can do sitting or lying down exercises and for others too- but of course

In this youtube video there are work outs  which you can do while sitting . Many muscle groups are engaged and these are good exercises.

Of course you don't have to take out all the movements fully if you cannot manage them as  well-trained Donovan Green in the movie. As always, It's good what you can do. For example , if you don't have the strength to walk as far as recommended, it is enough what you manage. For many small paths inside the home is good training.