My phone is bent

I've run into a similar situation with an iPad Mini where the frame was bent and I was wondering if I needed to replace it or if it would be possible to straighten it, so I've had some experience with this.

First of all, yes, it can be done; I got the iPad apart and was able to straighten the frame. The most important thing to know is you must remove the screen. Glass only bends so much before it breaks, so there's no safe way to straighten out the frame with the display mounted. Once you have the screen off, then you're free to flex the phone as needed to make it flat again.

I wasn't able to locate a written, iFixit-style guide to replacing the screen on your phone, and frankly most of the YouTube videos I viewed were poorly and unprofessionally done. The one I thought was worth looking at actually went one step further than you'd need; they were replacing the front glass of the display, so they separated the digitizer from the OLED display, which obviously you'd want to skip doing.

Xiaomi Poco X6 Pro Broken Touch Glass Fixed With Professional Way!! #PocoX6ProBrokenTouchRepair - YouTube

Anyway, if you follow the video and get the screen off without breaking it, the next step is to straighten the frame. Lay it on a flat surface and get a feel for the high points on either side. Drawing an imaginary line between those points, that'll be the line you want to bend back. Start gently with a small amount of bend, then check it with a straight edge. Keep doing a slight bend and check until it's as flat as you can make it. Verify the flatness on all four edges, and again lay it on a flat surface and make sure it lays perfectly flat.

Once you're happy with it, clean the adhesive from the frame and the screen then go ahead and follow the video to reassemble the phone.

That's about the best advice I can give you; hope it answers your question. Good luck and be sure to come back and let us know how it all turns out!