These units shipped with up to a 2TB NVMe drive according to the maintenance and service guide http://h10032.www1.hp.com/ctg/Manual/c06155404
Best option is to purchase an external usb harddrive, create a recovery image to that, replace the internal drive and then perform a system recovery. It is good practice to backup to a local source anyway so having an external drive is a life saver.
If you find the information provided useful or solves your problems, help other users find the solution easier by giving kudos and marking my post as an accepted solution.
I am a volunteer, offering my knowledge to support fellow users, I do not work for HP nor speak for HP.