wut do u ahve to do to use the internet on a laptop..?

[italian_singer_1989]

my frend is selling his little laptop.. u kno those new little ones u can carry with u...well im buying it off him...and i have a desktop computer..sumtimes i need to use it upstairs cuz my dad yells at me for being the computer too long..so i rater use sumthing in my room..what do i ahve to do to use my internet...can i use net from my dekstop if it will pick up?..or how does it work..do i have to buy sumthing?... i have rogers..motorola modem