MacBook Pro will not let me use the Internet

Any other devices connect to WiFI and have internet access for comparison?

To trouble shoot further you can:

—Try a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. Login and test. Reboot and test as caches get rebuilt.

In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.

This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.

—Test issue in another user (or guest user) account  https://support.apple.com/en-us/HT204443

This will tell you if it a universal issue or isolated to your user/admin account. 

you can Try resetting NVRAM/PRAM http://support.apple.com/kb/ht1379

Try resetting the SMC https://support.apple.com/en-us/HT201295

If your Mac doesn't connect to the Internet over Wi-Fi - Apple Support

or

Use Wireless Diagnostics on your Mac - Apple Support