Please I can not install the ethernet on my computer, do you can help me

You will have to open up your network connections click start control panel network connections this may vary depending on your operating system look for local area connection if you see a red x or a yellow exclamation or question mark you will need to update or install the driver or it could be firewalled or you could click start control panel administration tools computer management device manager look for network adapters + expand Ethernet driver if you see a yellow question exclamation mark or a red X you will need to update/reinstall the driver for the device if you computer came with a motherboard disk the driver could be on it
if you dont have an ethernet driver you will need to download it
http://download.cnet.com/Realtek-RTL8139-Family-PCI-Fast-Ethernet-NIC/3000-2112_4-91313.html
if these driver packages are not right
http://download.cnet.com/2000-20_4.html
on the home page you should see a search tab just type in what you are looking for
(be precise) exclusions - / ? you might have to try a few times to get it right
also the download software finder under that there will be a list place a tick in the box of any one you want/need
all software windows software mac software mobile and web apps

http://majorgeeks.com/downloads35.html

also this link will provide you with many freeware and share drivers

hope this helps you