Start of my Journey: losing weight with chronic foot/ankle pain

Hi, so I’m 21 and have been dealing with some pretty severe foot/ankle problems for almost 2 years. During the worst of the pain I found myself not able to walk a whole lot (and actually spent months immobile completely) and I allowed myself to fall into a time of not caring about anything and gained 25lbs. Before this in highschool I loved running so it takes a lot not to be depressed about the whole situation. Now at my highest weight (since middle school) I’m starting at 141lbs and my goal is at least 130lbs, but I’m really hoping to eventually reach 125lbs. I’m 5’4 so I believe thats around a bmi 21-22. My only form of exercise is walking, since my foot/ankle doctor advised me that jogging/running is out of the question, but I do work and take short walks frequently so I get anywhere from 5,000-10,000 steps throughout the day.