u/KAZO69420

So I bought a 2011 ninja 650r and it has 23k miles. When I bought it she started up fine and was running fine but smelled rich. Then when I took the ride home it would die every time I try to down shift and now womt even stay without a jump pack.i checked rhe oil and just straight gasoline smell poured out the bike and the air filter was completely deteriorated and assuming went into the engine. The air box had oil all in it and so does the throttle body. I’m lost and completely uneducated enough on bikes. Please help it would mean a lot