I have used ethernet cable to connect to a modem for internet connection to my raspberry pi. I am getting error messages when trying to open a page. when i tried 
`sudo ifup eth0` i got this error message:

```
listening on LPF/eth0/b8:27:eb:82:78:a9
sending on   LPF/eth0/b8:27:eb:82:78:a9
sending on   Socket/Fallback
DHCP discover on eth0 to 255.255.255.255 port 67 interval 6
DHCP discover on eth0 to 255.255.255.255 port 67 interval 12
DHCP discover on eth0 to 255.255.255.255 port 67 interval 15
DHCP discover on eth0 to 255.255.255.255 port 67 interval 20
DHCP discover on eth0 to 255.255.255.255 port 67 interval 8
No DHCPOFFERS recieved.
Unable to obtain a lease on first try. Exiting.
Failed to bring up eth0

```

Thank you.

PS: I wanted to play youtube on my old tv.