Buy older proven reliable car, learn to drive it and the course. Race it 1 or 2 years and learn everything I can. Then go after something serious and hopefully have some sponsors to help by then.
Or if it's a million for 1 shot, buy the best car within budget and a older car to beat up prerunning and learning the course. Prepare the best you can, try and get someone with experience on your team and send it.
I guess I'll never race cause I can hardly afford my 4 banger turd box let alone 2 race cars😂