It's good that you've done the rough math on it. I'm a SWE and right out of the gate at 100k might be a bit tough, though you can easily get there and more in a few years if you're aggressive about career growth. As for cutting expenses, you are onto something with a LCOL area but I'd also suggest househacking to generate extra income if you're ok with being a landlord. A friend of mine in the FIRE community does this with a big 4 br home and does really well.
Additionally, look at the military as an option, since at least in the US, the college tuition and healthcare options as a vet is a huge cost savings. But, it's a time commitment, so not for everyone.