WiFi Configuration:

Knowing your WiFi Band:

If you aren't aware about which GHz your wifi is , then head over to Settings > Network and Internet> Internet> click on your wifi's name , it'll show you your WiFi's GHz on that page under "Frequency" .

Now based on that information , go to Network and Internet> Internet> Network Preferences , and select the GHz that matches your WiFi.

Explanation about MHz Bandwidth:

High MHz = High Speed, Less coverage and Low stability.

Less MHz = High and Strong Coverage but at comparatively Lower speeds.

So for 5GHz WiFi Users:

80 MHz will give you the highest speeds but with less coverage in case you are far away from the router , that could be a problem

40 MHz will give you far better stability and coverage at a bit less speed compared to 80MHz, it's more like a balance between speed and range/stability.

20 MHz will give you best range and stability for your wifi signal strength, the speed will be less compared to the other MHz(s) but stability and range will be the best and your wifi will be uninterrupted in case you are far from the router.

And For 2.4 GHz WiFi Users:

40 Mhz will give you the highest speeds , but you could have issues with range and stability in case you are far away from the wifi router .

20 MHz will give you the best stability and range no matter how far you are from the wifi, but the speeds will not be the best, but it'll be good enough without any interruptions.

Now based on the above information, select the Bandwidth of your WiFi and choose 80 ,40 or 20 MHz Based on your needs.