Help with older computer with discontinued Wireless adapter

Ive been trying to find solid answers to this for some time now. I was hoping someone here can help.

Im using an older toshiba laptop with windows 7. I cant update to windows 10 bc it says "wireless adapter not compatible" or something like that. Also, Im noticing my wifi signal fluctuate like CRAZY sometimes..It will hold at 144mbps, then drop to 15mbps, than 56mbps and back to 144...sometimes it goes to 300mbps and 270..etc.

Ive been trying to find out whats causing it. I cant find a driver update bc it says my driver is discontinued.

Intel centrino advanced-n 6200 v 13.2.0.30

I dont know what to do...