Ngl, climbing becomes a lot easier if you are lighter. But also, there’s nothing stopping you from enjoying it at a heavier weight - you just climb routes with an easier numeric grade. And there are various climbing disciplines that are less disadvantageous to heavier climbers, like ice climbing or mountaineering. If you want to take a really traditional approach, you could enter climbing by way of hiking and backpacking, which are also a lot of fun and have a decent amount of skill overlap.
Also, I have no science to back this up, but I just intuit that when you consistently do activities like hiking, running, and climbing where lower body weight is advantageous, your brain notices and predisposes you to lose weight.
So give it a shot!
Upwork is a website where you can search and hire freelance software devs - and there are other, similar sites out there as well. Vetting the person you hire will be a whole process in itself.