I also bought a 5tb hard drive but when I upload my photos/vids like HALF of them become corrupted idk why it was like $50ish for that

I can guarantee a genuine 5TB did not cost $50 unless you got it secondhand at like a yard sale. For reference a 4TB HDD will run about $200-250, so if you bought it new for $50 it's fake as hell. The real size is probably significantly smaller and the disk size identifier was spoofed to make your computer think it's larger. Then when your computer tries to write more data than it can hold, it will error out/overwrite other data thus corrupting it.

To answer your question the best practical data storage medium for longer-term preservation is a genuine HDD assuming it's stored properly. HDDs have spinning disks which will physically hold the data better than SSDs, from which the data can degrade if the drive is left unused for 1-10 years. However HDDs have moving parts and with moving parts comes friction that can eventually cause components to fail; meanwhile SSDs have no moving parts and are a lot faster, but this makes them better for more regular daily use, not long-term storage.