You will run into problems and severe deficiencies in this old version of Lightroom.
You may be able to download from this link-
Lightroom 6 End of Support
You must have a Serial Number (and do not install the Adobe Creative Cloud Desktop App!)
You may strike 'Activation' problems that only Adobe staff can fix.
A subscription to the latest version (11.4.1) in the Photography Plan (20Gb) is now the only recommended install for 'new' computers.
$9.99 PHOTOGRAPHY PLAN (USA)
Regards. My System: Lr-Classic 12.3 Photoshop 24.5, ACR 15.3.1, Lightroom 6.3.1, Lr-iOS 8.0.8, Bridge 13.0.3, Windows-11.