It’s downloaded from game pass, no disk

By "hard disk" he/she meant hard drive or SSD. Your internal storage device might be faulty. Also, Destiny 2 is no longer in the Game Pass but I guess you meant you downloaded it from the Xbox app.

I meant I downloaded it for free on Xbox, and the SSD isn’t bad because I can load and play every other game I have without a problem.

And I just went through the process again on it and it says it has unreadable game content and that’s the reason of a full reinstall but it’s said the same thing every time I’ve done so…

[quote]And I just went through the process again on it and it says it has unreadable game content [/quote] That 100% sounds like your device is faulty. If it's not installing something and/or constantly failing to read data, there is an issue. Just because you can install other games fault-free does not mean there isn't an issue with your device. Check out [url=https://help.bungie.net/hc/en-us/articles/360058647971-Installing-Reinstalling-and-Updating-Destiny-on-the-Xbox-Series-X-S]this article[/url] for support. You may need to reach out to Xbox Support. http://support.xbox.com/contact-us