I found out that it isn't the router/modem that's causing the problem. If I connect the ethernet cable to this laptop specifically, it still works.
From what it looks like, the computer isn't receiving the dhcp address from the router and keeps giving itself a local IP.
I've already tried the following
cmd prompt "netsh winsock renew"
cmd prompt "ipconfig /release ipconfig /renew ipconfig /dnsflush"
Restarting the router and modem SEVERAL times.
Manually putting an IP instead of the obtain automatically option
Disabled and re-enabled the Local Area Connection internet adapter
Checked on the gateway website (through this laptop) and saw that this laptop was the only one accessing the network
Yet again, help would be appreciated :/