Installing network drivers on a Windows 7 machine without an active internet connection requires downloading the necessary files on a secondary device and transferring them via USB. For the most reliable results, you can use specialized offline driver packs or official manufacturer installers. Top Offline Installer Tools for Windows 7
Basic UI that looks like it belongs in the Windows XP era. network adapter driver windows 7 offline installer best
Identify the network adapter model on the target PC: Installing network drivers on a Windows 7 machine