Hi
Most laptop adaptors are sealed switch-mode power supplies. If it has a damaged connector or cable you could fix it if you can solder. But you will find cheap Chinese knock off adapters on eBay for less than the price of the parts and used genuine adapters at a decent price. You probably aren’t fixing it, but you should ensure the power supply is the issue by checking the voltage across its connector if it does not have a physical problem.
Best regards,
Robin