The wifi button will not slide to allow connection to wifi

Hi Kaccy01!

I understand that your iPhone Wi-Fi will not turn on, and I'm happy to help.  Please make sure the iOS software is up to date:

Update your iPhone, iPad, or iPod touch

Also try restarting the device:

Restart your iPhone, iPad, or iPod touch

Also try tapping Settings General > Reset > Reset Network Settings. This will reset all network settings, including Wi-Fi passwords, VPN, and APN settings.

Cheers!