05 landcruiser. An I screwed?

Even it passes the CVRT that'll still need to be replaced. It comes down to what else needs fixing after the CVRT

parts that bolt on to body can be replaced go online & get a guide price of those parts once the body is sound its worth saving after all its a toyota you cant kill them.

To my mind, there's no such thing as a stupid question. What i would say though, there have been some terrible accidents over the years with home mechanics working under cars outside the front door. And if THAT beast fell on you, it would be curtains.

The mechanic with the lift is the place to go. It'll cost a bit, but might be better than having to scrap it, might be. As you say, lesson learned, but don't throw the baby out with the bath water, it might be salvageable for less then an arm and a leg, and then you'll KNOW its good to go for a few years yet.

Best of luck.

Not a stupid question at all. Realistically unless you have proper equipment you shouldn't be going under a car. The sort of jack provided in car kits is only suitable for lifting an already loosened wheel off the ground to change it. Never, ever put a body part, especially your head, under a car up on one of these jacks. They are just not safe and completely unsuitable for doing any work on the underside. Many people have caused themselves horrific injuries due to collapsing jacks.

Do as your mechanic says, put it through DOE and take it from there. Once you have an overview of what is needed then you will need it properly assessed, Your mechanic really should have informed you of the condition of the rest of the car but for a full assessment any areas of concern will need all the rust and crud removed to see what is left.

Remember rust expands to many times the size of the steel it has formed from so surface rust can look worse than it is, until it is down to bare steel you won't really know how bad it is. Parts can be replaced but it will be the condition of the chassis and bodywork that is most important. Before spending money on any of it you need to know everything that is wrong, no point getting parts replaced and then finding out it will cost silly money to fix a rotten sill.

No one here can give you a comprehensive answer from one photograph. And if they try, I wouldn't be listening to it.

Take it to a 4x4 specialist, it will be worth fifty or a hundred quid to get it looked over and assist your decision whether to change out components and save it, or sell it for parts.