List down and explain all type WLAN troubleshooting?

Wlan is means wirless local area network,
its is u in school,hotels,company.
wlan connective is in laptop and presenlty get in mobile that option call as wifi.
wifi option in laptop connect to wlan. while cofira wlan its show that wlan connect want to kept crediational to connect wlan thought wifi have to ask password..
wlan have a some option like if like reset > its use last time use and get in with that crediational then press on reset button.