New PC

Think I might have to get a new PC : (
Good part is it will force me to get the latest norton and the latest IE
I’m thinking it makes no sense to go with anything older than Windows 8.1
I have Internet cable service and the modem/router has wifi
I know that I had password protected the router (as well as the wifi connection)
But if I get a new PC how do I pass word protect the modem/router?
Would the pass word still be in effect?
Stupid question I know : (