- You have the option to choose to remove everything or not.
- It may not, but it does fix some.
- You need to connect to the internet to activate automatically. If it can't, you would need to re-enter the product key. Or if you had a digital license, just enter your Microsoft account to activate.
- Since I haven't done a reset, I can say no.
- During reset, plug in your adapter. If you meant after reset, it may or may not.
If you can't reset, you can do a reinstall to fix issues. Reinstalling fixes lots of issues, but you have to go through the OOBE even then.