My cOmputerr wOn.t let me dOwnlOad anythinq/ hOw can i qet a prOtectiOn plan/ if it wOn.t let mee?/?

i have a dell. cOmputer && i think i qO.t a virus how can i qet ridd Of it iif my cOmputerr wOn.t let me dOwnlOad?!!-/