How to fix broken features on my eBay iPhone X 256GB

got an iPhone X 256gb to replace a 128gb 13 which it has done its job well. Long story short it’s from eBay. It came with most of the features broken? No volume button works, no vibration, no silence switch, no video is playing unless I connect it through a pair of Bluetooth headphones and that on everything besides TikTok and Reddit media formats.

[Re-Titled by Moderator]