iPhone 12 Pro Max Wi-Fi problem

My Wi-Fi will not turn on. I’ve tried several different things to get it to turn on. I’ve shut it off and on several times. I reset all my settings. I tried factory resetting it & when I go to enter my password for my find my iPhone it says it failed. I don’t know if it’s because there isn’t Wi-Fi or what. I absolutely cannot figure it out & I don’t remeber the number for it so I can’t call apple support.. someone please help, I don’t want to have to buy a whole new phone.