Unlikely without an adapter, best would be to get a good SSD with SATA interface. You can only have 1 disk (either SSD or HDD) . Read the guide carefully - Step 34 Mac mini Late 2014 Hard Drive Replacement
"It was scratched with a screwdriver" Are some traces broken. You could carefully draw them with a pen or reconnect and solder. Post an image here? so experts can see and help!!! "it’s been out of stock since th" Depending on your country search in eBay or local market place for another Acer R11 (with display broken or other problems). Replace!
Which model? See this: Acer Chromebook C720 Solid State Drive (SSD) Replacement Google/look in youtube - most likely it is a loose contact that SDD is disconnected. Gently unscrew - check everything like loose cables/connections. Try. alternately, the SSD is damaged. Buy an replacement. See Acer Chromebook C720 Solid State Drive (SSD) Replacement Post here again…
"I think this whole situation all started when I first opened the back of the phone and put it back. Please help me with how to fix it and what not to do with the phone." Electronics are very fragile. Just be careful - but good news - u became a good hobbiyist and reparier - learn by reading the different teardowns in ifixit - be gentle when opening phone SMACKING is not to do!!! "I smacked it on my lap to work and it did."