You can check the battery model (top-left of the battery), for our case HT03XL, with this reference you will be able to get the propper replacement.

If you have the replacement you can unscrew the 5 P1 Philips screws. The top part will have the connector you will need to disconnect to remove the battery. You can follow HP official video to remove the battery

Connect the new battery and screw again the 5 screws.