I did the BBC couch2k via mobile phone app course during Covid lockdown after 40 years in office job, but was daunted starting aged 60. I was not overweight but unfit with a slight muffin top layer of fat accumulating around the midriff . I found the programme was encouraging and not too difficult to get up to 5k distance with determination. I jog on the flat rather than run, and avoid hills when I first started, and did buy decent running trainers with gel soles which minimises risk of kneed injuries from impact from running on pavement surfaces. Brookes trainers are expensive brand but are good and you can get last year's models a bit cheaper. It's worth getting 'gait' assessed if you can find a sports shop that does this.. I still run 5k at least once a week and usually twice. I do 5k parkrun each Saturday over mix of grass and tarmac trails most weeks . Have now added once a week sea swimming, occasional cycling and started tennis sessions with a beginner's group, and do feel better for it but it is an effort to make the time while working full time. When I retire, I will try to do add some resistance training with weights a couple of times a week.