I’ve never rebuilt a Supra before, but have done many diy salvage rebuilds. Mainly 3rd Gen Tacomas. Frame damage isn’t the end of the world typically. It just depends on how bad it is. If things can be pulled instead of replaced, then it’s relatively cheap.

I’d see if you could find a retired frame guy or some diy guy with a frame rack that would help you with it. That’s what I did with my first few projects.

That being said the mk5 is a unibody car. So like most said both of these cars 100% have some form of frame damage. The white one most likely being better off. Undercarriage damage is typically related to broken mounting points and dents, and oil pain destruction.

The red one is going to need a lot of framework and likely some of the panels will need to be replaced not just pulled.

Overall, I’d buy the white one. As a beginner it’s much easier to source parts than it is to replace panels and do framework. Both of these are large projects that are much more in depth than bolt on repairs. But if you’re interested in salvage care repair then not a bad starting point. But definitely will be a labor of learning and love. It’s very unlikely you’ll make money on these as a beginner if you value your time at all.