Hi:
Below is the link to the motherboard specs page for your PC.
Look under the Jumper Settings section for how to clear the CMOS (reset the BIOS).
https://support.hp.com/us-en/document/c03135925
Looking at the picture of the motherboard provided on that page, it appears the jumpers referenced in that section are located above the SATA ports. Look at the lower right section of the picture. You have 4 sata ports and it shows the two blue jumpers about 1/2" above those in the illustration.
On the full size motherboard, these jumpers will probably be further away, but you should be able to find them.