Take the insurance money and start looking for another Mustang. Fixing it yourself will cost more than what's it's worth. If you don't have all the proper tools and know how and time plus a large place to store parts, just isn't worth it
Need more pictures from multiple angles to help from here.
I'm no expert in body work, but I do some from time-to-time as part of my job and know how to write an estimate. Get some more pictures, including with the hood up, and I'll see what I can do, but honestly, a V6 car that insurance is calling a total loss is probably better off being exactly that.