WiFi not detecting signal

Unless we know the model number we can’t help with your specific model, but there are a few things you can try now if possible.

The first thing I would do in this case is try the drivers and see if that helps. Download them on another machine - or Ethernet and then remove and reinstall the driver. I would download it from the wireless card manufacturer and HP if possible, depending on if the card has drivers direct from the manufacturer - some of the Intel cards like the 6235 do not have drivers directly from Intel, but others like the 7260AC do for example. HP usually uses Intel in their higher end business laptops, so it may very well be Intel unless you bought one of the cheap configurations. Consumer machines (and some low end ProBooks) use Ralink (purchased for IP by an SoC manufacturer. Most cards are EOL and struggle in Windows 10) or Realtek (may find drivers on manufacturer website, but they tend to be "low-end" cards which can be problematic with newer routers with modern support, if the legacy backup options aren't well integrated).

If that doesn’t work, you will need the service manual to find out which cards are on your WLAN WL since pre-2013 HP Business machines prior to the Haswell EliteBook series are infamously known for having a wireless card whitelist (HP uses the all too common FCC lie Lenovo loved up to the same point, they admitted it when they dropped it in 2013!) and was there to protect parts sales. The issue is their Business BIOSes have been signed with a checksum for years and verified, but 2010+ is ALL RSA signed and the machines verify the RSA signature against the “validated” private key (UEFI SureStart machines are impossible to modify, they will not run the modified BIOS and insist you restore to boot). It’s the same reason I can’t modify the nc6000 BIOS to nuke the WL from orbit entirely to install a non-HP card (MADE BY HP, but not on the whitelist). When it comes to HP, ALWAYS BUY A MID SPEC MODEL WITH HP BUSINESS to get the Intel wireless as an FYI - even Haswell EliteBooks just in case but if you get a Broadwell or newer unit, it's less detrimental as those are WLAN whitelist clean confirmed. This isn’t like a lower end Dell where it can come with a DW1506 (AR9485) or a BCM based card like the DW1501 (BCM4313). I can buy a NOS Intel 7260AC (or a used Intel 6235) and get better wireless with little trouble.

I’m not sure about the WWAN situation with HP on Haswell EliteBooks, but chances are it’s still there due to more real FCC issues and carrier concessions HP has to make for the laptops to be taken on the big networks. My phone plan includes a hotspot, I literally use my phone if I need it.