Good luck on your quest.
I only started GLPs after losing most of the weight from 145kg to 75kg, but have found they make keeping the weight off much easier, and of course every previous weight loss attempt had ended with me regaining the weight but 3 1/2 years later this time still normal BMI.
I think this is where GLP drugs shine, maintenance, as making a mammoth effort with diet and exercise to lose weight is hard but not as hard as keeping it off it. But losing it with GLP drugs and then staying on them basically keeps the weight off long term, not even surgery is that good in terms of long term maintenance, although it can cause even larger weight losses. The fact that keeping the weight of long term is actually realistic is a good motivator, especially if you have previously lost weight and regained it.
There really is a lot of individual variation in responses to GLP drugs, a small percentage maybe 5-10% do not lose much weight, and some lose lots even on tiny doses, and some get intolerable side effects. You really just have to start and slowly build up doses to find out how well they work for you, and hope for the best. For the vast majority these drugs are a game changer for obesity.
On average tirz causes 25ish% weight loss in a year or so and reta 29%, so reta is a bit more effective, but probably has slightly higher rates of side effects. Given you want to lose a lot of weight, reta might be the better choice, but tirz is fairly close behind in effectiveness.
I can relate to the exercise issue. Intense exercise can be profoundly aversive to someone who is unfit, basically making you feel so horrible it becomes very difficult to force yourself to keep doing it. The most effective way to start and keep going is to make it easy not hard. When I was still overweight and profoundly unfit, I just decided I had to go for a 5 minute walk every day, basically making it so easy there was no reason to avoid doing it, and almost no chance of it making me feel exhausted or ill afterwards, and I gradually built up the time over several months and turned it into a habit and eventually got to 3 hours or so a day after several months and quite a few kilos lighter which helped a lot, without the kind of aversive post exercise fatigue that I had typically had when attempting exercise. It does not matter what exercise it is , but the general concept is to lower the barrier to doing it so low that it is super easy to do and you are less likely to avoid it and have a decent chance of turning it into a long term habit. But you have to do that minimal bit every day or a certain number of times per week. I did not even try to start walking until I got to 115kg as even then my feet hurt like hell just from walking 5 minutes, sometimes it is reasonable to wait before starting up exercise if severely obese.
Eating a good diet on GLP drugs is a good idea, but they work anyway even if you don't just by making you less hungry so you eat less, they probably work better if they are not fighting against a high fat high sugar diet, but they tend to encourage you to improve diet quality anyway. Eating at least 1.5grams per kilogram of body weight of protein is a good idea to minimise loss of muscle mass while losing weight. And high protein intake is more filling per calorie than any other food which helps with hunger and weight loss.
