We have found 2 possible solutions to your problem.
Before you start this troubleshooting guide you need to check one important thing:
Can you use your modem as a Wi-Fi hotspot?
Yes
No
Why do we ask this question?
It's important to find out if you can use your modem as a Wi-Fi hotspot. If your modem doesn't have an internet connection, you need to solve this problem first. When the problem is solved, you will most likely also be able to use your internet browser.