Try to ping a public IP, open Command Prompt, type ping google.com and then press Enter.

ping google.com

Pinging google.com with 32 bytes of data:

Reply from google.com: bytes=32 time=36ms TTL=242
Reply from google.com: bytes=32 time=35ms TTL=242
Reply from google.com: bytes=32 time=36ms TTL=242
Reply from google.com: bytes=32 time=37ms TTL=242

Check the TCP/IP settings

To check TCP/IP settings, use ipconfig /all command line. The part of the result looks like below.

IP Address. . . . . . . . . . . . : 192.168.10.18
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.10.1
DHCP Server . . . . . . . . . . . : 192.168.10.1
DNS Servers . . . . . . . . . . . : 63.240.76.4
204.127.198.4

1. Make sure you have correct IP range.
2. Make sure the Subnet Mask is the same of the router.
3. Make sure you have correct default gateway.
4. Make sure you have correct DNS.
5. Make sure no filtering in the router to block the Internet access.