Even though my MacBook Pro is connected to Wi-Fi, I cannot use the Internet

Read If your Mac isn't connecting to the internet over Wi-Fi.

VPNs and "anti-virus" junk are the most common reasons, but please review everything in that document and write back if you don't get anywhere.

next try 'the Hotel trick':

type this into your browser address box:

1.1.1.1 and press return

if you get the CloudFlare** splash page, you have a good connection to the Internet, but your Domain Name Server (DNS) numbers may be missing, stale, or invalid.

**CloudFlare is NOT part of the solution here, they just have the easiest-to-remember all-numeric IP Address that always answers.

It could be your router.

If you look on the bottom or side of it it should have a number on it This is an example, yours will be different. 123.123.1.123. represents the router IP address. Type that into your browser and see if you can bring up the router interface and see if the router is connected to the internet.(Look for a WiFi tab) Be careful not to change anything. If your router isn't connected to the internet call your ISP.

AlWier--

The current Router IP address is typically issued by the Internet Service Providers UPStream Router, so it is dynamic.

No numbers stamped on the label of the device will suffice in getting you a connection, not even to the Router itself.