Trouble with network password

I bought this computer at a school auction and it has a network password on it how do i get it off or find out the password. I was told that they were suppose to reformat it before they sold it but they didn’t and now i have the computer at home and can’t use it. I tried to reformat it but it won’t let me do nothing cause it keeps asking for the network password. It won’t even boot into safe mode. It is running windows 98. Thanks for your help as I need to finish this so i can give it to my nephew for his birthday.