My WinRAR expired 7 years ago. It runs the same it did back then. Don't worry, it's a trialware without a limit. The software expects you to pay but doesn't force you to buy it.
it's technically not free, but it might as well be, there's no punishment for when your license inevitably expires, except for a pop-up window that shows up everytime you open a file that you use WinRAR to open