Movement
Walks, parkrun, first weights
Walking a parkrun on a Saturday morning
parkrun is a free weekly 5k, and walking the whole way is allowed. Someone always finishes behind you.
The ten-minute walk after dinner
A short loop round the block is an easy habit to start, and it gets you out of the kitchen once the plates are done.
A first week of strength work at home
Two light dumbbells and a mat are enough to start. The hard part is picking a time and keeping it.