How do I bend back my computer?

You will have to disassemble your laptop and see what’s broken and whether it’s fixable.

With the exact model number you should be able to find a disassembly guide, either here on iFixit or elsewhere. You may need to consult one or two to get the full picture.

Plastic parts of the case frequently break, in fact this is the usual cause of a broken hinge (i.e. not actually the hinge itself at all). Two-part quick setting epoxy glue is the best method of fixing, provided it has enough surface area to grip onto and provided you can accurately reposition any parts that have actually broken off, especially bushes that screws screw into.

Alternatively you could always look out for another laptop of the same model offered on eBay as “spares or repair” but with an intact case, and swap over as much as the guts as you need to.