Network Administrator?

I think your best bet would be to set a password on your computer. He could find your computer on the network, but if you have a password he doesn't know then you should be fine. When he needs to set up your computer to the network then you can type the password in for him. So I think you might be able to do this. He may only work with the router and other parts of the network. I'm still learning about these types of things though. So I'm not positive that I'm right.

If you let your boyfriend set up the machine, and he has an administrator account, there is nothing you can hide from him. There are two things you can do. Never let him have physical access to the machine Pay someone to set the machine up with you as administrator and remove his access. Since you are not experienced in computers, I do not reccomend that you do this yourself. You will most likelihood end up locked out with no way back in, which would be no fun at all Good luck

If your home internet uses a wired router you can just plug in to it and you will have a connection. If it is wireless you will need to do a search for wireless connections and enter the encryption key to connect. All you need him to do is tell your the key. Set a password that is difficult to guess, and does NOT relate to anything to do with you. No birthdays, names, addresses or phone numbers. Then start the machine is safe mode by pressing F5 during boot. Go to users in control panel and set the same password for the user administrator. This way you will not forget it, but he will not know it. If you do not do this he could log in as administrator and see everything.