people often say exercise is counterproductive to losing weight
Weird! Not true. What is true is that you can't out-train a bad diet (this was what my personal trainer said to me at the start of working with him).
I've always done cardio stuff, but never serious lifting. have been doing concerted weight/strength training for about 7 months now and my body shape hasn't changed so much as tightened up, and my outline looks quite buff now. There's still fat inside that silhouette (I'm almost 60 so it's harder to shift) but there's visible muscle definition eg in biceps, shoulders and quads, plus I experience being stronger. On a recent trip, I could easily lift my suitcase - it was grand being strong !
But I've also change the way I eat, and mostly stick to around 1500-1600 calories a day. Very healthy eating, though & I rarely feel hungry. About 2.5 liters of water a day as well.
Join a gym, get expert advice. You get injured because of a combination of inaccurate technique and bodily biomechanics not being perfect (none of us has perfect biomechanics). So you need to learn how to do things safely with good technique. A few sessions with a personal trainer would help.
Also, start really slowly. I never really got into running because I kept getting injuries. I have a lot of energy so I would start fast. And then my knees or my hamstrings would hurt so much. So use a Couch to 5k graded training app, or do interval work - 1 minute running, 1 minute walking and build it up.
In strength training do the same. There's a scheme "5 x5" I think it's called where you build strength by lifting in 5 specified lifts, and add a bit of weight each session, with 3 sessions per week.
Also pop into the Weights Room here on MN. Some really helpful people - I've learnt a lot from reading that forum.