Not to worry, the most straightforward way to hook up your printer is to simply uninstall and reinstall the printer according to HP's instructions. This is not scary at all. And the easiest way to install the printer is to use a USB cable to attach the printer to your computer.
You're in luck because HP is really good about instructions. In addition to their published instructions, they have videos on their website to help you install their printers, and you can access their technical support, and they have their own community forum - just like Microsoft Q&A - where you ask questions of other HP printers owners. That's probably the best place to get advice, but we are also glad to help.
The key is to tell us the exact model of HP printer you have, so we can find the correct instructions on HP's website, and probably videos we can point you to. If you like, here is HP's official Printer Support Community.