I can't connect my iphone 6s Plus to my wifi.

I'm having trouble connecting my iPhone 6s Plus to my WiFi and Bluetooth speakers, among other things. I've tried everything I can think of to fix it, including a network reset and a factory reset, but it still doesn't work. Other than what has been stated above, the phone has no physical damage or other concerns. I'm not sure what else I can do to resolve the problem.

Attached below is what pops up whenever I try to connect to my network.

Please help me and advance thanks!