my iphone 4 isn't connecting to wifi. It says it is connected, but nothing will load. Other people in my house are connected to it, so the internet is working properly

Hello there, Sliv95.

The following Knowledge Base article provides very pertinent steps for troubleshooting your issue:

iOS: Troubleshooting Wi-Fi networks and connections

http://support.apple.com/kb/ts1398

After performing the primary steps under "Resolution", if the issue persists review the following section:

Unable to access the Internet while connected to Wi-Fi

1. If you're using a public or commercial network, you may need to log in or subscribe.
2. Check to see if you have a self-assigned IP address:
   1. Tap Settings > Wi-Fi and locate the Wi-Fi network to which you're connected and tap .
   2. If your IP address is 169.254.xxx.xxx, you may not be able to access the Internet.
3. If you do not have a self-assigned IP address, see if other Wi-Fi devices on your network have Internet access.
   • If they do not, consult with your network administrator or ISP for further assistance.
   • If they do, reset network settings on your device by tapping Settings > General > Reset > Reset Network Settings. Note: This will reset all network settings including:
     • previously connected Wi-Fi networks and passwords
     • recently used Bluetooth accessories
     • VPN and APN settings

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro.