If they have it available in the market, then its possible. If you dont mind thicker bezels and less colors on screen, it should be okay. But you may lose true tone
This laptop does not have a graphics card. It is integrated to the CPU. Use this link for the HD Graphics driver specifically for your hardware: Intel® HD Graphics driver for Windows* 8/8.1 (64-bit) Hope this helps
If you have a multimeter, check for voltages on the fan connector to see you getting voltage. Best case scenario you just replace the fan itself and works again. Worse case scenario, you might moved the resistor or capacitor during the usbc replacement. Do a visual inspection on the board
Maybe the replaced potentiometer could be bad from the start. My recommendation is to see if you can find a good quality potentiometer and see the drifting goes away again
Based of what you said, the phone turns on because it was charging but the screen flex cables are very fragile. It may look like the connector is not damaged but inside the connector is copper wires that you cant see. you might've broke the copper inside of the connector.
There is a possibility that the battery is starting to die out. Possibly need a replacement Since its 2010. Batteries tends to go flat after 5-10 years