It’s not important to have one same routine for everyday, you can set targets for the day according to your convenience. Just have in mind what all you want to do in the day.
Make sure you do the tasks. At any time of the day.
Slowly you will get back on track, pick one or two things initially then gradually move towards planning your entire day.
You can start by making small or 1/2 changes. Dont try to have a completely new routine. Take small changes and build them to something you want.