Hello, I just registered. What people find out about my location/my PC has always bothered me, I was surprised for the 1st time when a website showed my PC model to me. Not like I do anything ileagal in the web

,just curious what info people can actually retrieve about me.
So Shall I start with the questions?:
1. So websites can find out my ip as well as my proxy ip and my city?
2. Websites can find out my PC model as well as my PC's resolution? (btw, any way to hide this?)
3. Websites can find out other websites I visit before them?
4. Is a MAC address available for ANY device? So people can find out that too? Why is there an IP address then?
Thats all I could remember fro now. Thank you for reading