Hi there, thanks for your question.
To connect your printer to your wireless network, you can follow these steps:
https://support.hp.com/au-en/document/c04704963
You'll need your router's WiFi password, which HP won't be able to give you. You'll need to see if you can find the password written down somewhere, or else reset your router.
If you want to contact HP anyway, here's the link:
https://support.hp.com/au-en/contact-hp
Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.
Hopefully this helps! Please let me know if you need further assistance. Thanks!
