It (Mounjaro) works, in the sense that more than one study has shown that people on average lose a significant amount of weight.
The first 4 weeks is a dose of 2.5mg which is the starting level, not everyone loses weight on this dose, but it prepares you for the next level of 5mg. Once you've done 5mg for 4 weeks you can stay on that dose, or move up to 7.5mg, then 10mg etc until you reach a dose that works for you. It is not a quick fix, you are a similar weight to me and it will take many months to get down to a healthy weight. You would need to go into it with a longer term mindset and really think about what you will do when you get to a healthy weight and need to come off the medication. What will be your strategy for maintaining, for example.
I have found that I am now rarely hungry, and when I do eat, I want to eat healthy foods rather than lots of fat/sugar/carbs. I don't snack, I have no urge to do that at all which I find fascinating as I just used to graze on snacky stuff all the time during my work day. I get full really quickly when eating, which has meant I've learnt to do smaller portions at meal times.
You may find you get a big drop of weight initially, and then it slows down or even plateaus, or moves up then down a little for a while. It's important not to get dispirited by that.
Mounjaro is the most effective money I've spent on weightloss resources, including Noom and SecondNature which did nothing for me. I'm currently about 20lbs down from my starting weight in 5 weeks.