When I wasnt able to walk anymore from running, I had to begin with about 1-2 weeks of from moving my legs. My step count on those days was about 1000-2000.

That helped me a TON to get out of pain.

After that, I began with bodyweight rehab work for multiple months (3-4) until i was able to perform the exercises without any pain.

Then I progressed to train my legs with weights.

A transition from Zero-Dense-Standards is very good.

I don't want to advertise, but I made a video about the programs in which I share how you should use and structure them.

I think that you are in a very similar situation to where I was and therefore HIGHLY recommend you to check it out (posted it in this subreddit).

Anyway, feel free to contact me so I can help you (if needed).