Give yourself some leeway you had some stuff come up that clearly hindered any way to regularly excercise.
If walking is a good start then do that 2x a day for 20-30 minutes if possible. Or 10 min 3 times a day. Small steps (see what I did there).
Comes back to basics and common sense. Don’t cut out everything at once just small changes like more water less other drinks. Don’t go back for second helpings. Pause during meals and don’t watch TV or the phone while eating.