Not sure if it matters but I have Libreboot installed. It's the slot located next to the drive slot.
Also any other upgrade recommendations while I'm at it? I have maxed out the RAM and have an SSD. I am wondering if I should upgrade the WiFi card. I don't know if there are any limitations there.
Don't use a PCIe 4G/5G card if you care about privacy. That's giving whatever proprietary firmware is running on the baseband DMA access to your computer.