I'm not sure how to find the hardware or firmware version?

i have windows 10 PC and TO-Link Wireless N PCI Express adapter. 

The wifi connection is extremely slow and fluctuates a lot.

Right now it's 8mbps download. Sometimes it drops to 2mbps - sometimes 40+mbps.

I have verizon fios 500/500 so speed should not be an issue and fluctuating like this.

I use google mesh routers and have one 10 feet from my desktop with no interference. 

My mac laptop gets 60+ mbps download, no fluctuations. Also, my Iphone gets high speeds consistent and never slow speeds when my PC is slow. 

What can i do to fix this?