weird usb in basment, what i should do?

That's scary, I wouldn't even recommend checking it out ever again, the USB might be too old, corrupted or infected with viruses, or maybe a mix of everything I said. Tbh, it even sounds like an actual killer USB.

Also wdym by spongy, you mean, like, material/padding in the box, or, like, mold/fungus that grew inside or sum lol

i think it mold cuz the boxes still open and smell like poop rat also it kinda stinky and i think it might be mold also about the usb inside is was a memory card 1GB and also when i open on my phone it was a LOT of weird file dll and code also a textue and model i even have a dev log from 2007

Uh, depends where exactly you have found it.
Using USBs that are laying around randomly are not recomendet at all, because they could contain viruses or straigth up electronics to overcharge your device and destroy hardware.

If it was from your parents or stuff in some box or chest then the usb probably is just broken or something.
Might want to try out on a save device, like buyng a cheap used laptop that you don't need afterwards.
Something that is okay getting destroyed.

well sure i will buy a new laptop for thizx cuz iit kinda old now :v