Yes, you could but it would be terribly expensive. You’d be better off putting the money towards a new bike with disc brakes already fitted.
You’d need to purchase a pair of hydraulic brake levers/shifters, calipers, caliper mounts to fit to your front and rear forks, plus a new pair of wheels that you can fit the rotors to to that you will also need to buy, plus cables and oil, then the faff of fitting them if you’re not that mechanically minded, oh, and you’ll need a bleed kit too.
Yeah, as mentioned it’d likely be better a better idea to put the money towards a new bike… But if you are insistent on doing it yourself, there are plenty of tut’s on YouTube & eBay will probably be your friend for parts.
Just be warned that the videos make it look a lot easier (and quicker) than it actually will be.