Loud noise on startup

I have been having issues with my car, making a loud awful noise on startup. I have heard a few different options that could be, such as rusty exhaust, timing chain, and I have also been told to check my oil which has been changed and noise still appears. I initially thought it was only when it’s cold, which is how it started, but now if my car sits overnight or a few hours without any movement, a loud grinding, awful noise appears when I crank it again. It’s almost like a grinding noise as well as a rattle. Attached video of noise when cranking in comments!