yes those are genuine and you can install windows 7 OEM license. But, as
@Sarkar Bro said it's tied to motherboad so, you can't transfer license. Microsoft doesn't provide any support to OEM license.
yes you can access WI-FI. If your computer has WI-FI adapter then only. Update or install driver it'll work.
If your computer doesn't have any WI-FI card then you can buy USB power WI-FI card. It'll work.
Note: Windows 7 is 9 year old operating system and you can't download windows 7 from Microsoft website using OEM license key. You'll have to use the installation disc which you'll get with OEM licence. Those version are outdated and it's not easy to update. Microsoft changed some components in windows 7 windows update as a result it'll keep checking for updates but will never update (you may face this issue). You'll need to install update roll-up package manually after that it'll be able to receive updates from windows update. Windows 7 support will end on Jan 2020.
IMHO, it's better to install windows 10 or windows 8.1
Learn about licensing:
Licensing Logic: What's the difference between OEM, Retail and Volume Licenses?