THIS PAGE has all the info, as well as the downloads to make it all better again.
To quote them:
The Revival is Here
Download a fully functional version of No One Lives Forever (NOLF), No One Lives Forever 2 (NOLF 2), and Contract Jack with the latest community patches for free. Download the full game for PC now. Play single-player and multiplayer NOLF games for free!
You cannot buy a functional version of No One Lives Forever or Contract Jack any more. As a result, in an attempt to keep the community alive and attract new players, No One Lives Forever and Contract Jack Revival Edition are available to all for free and are a breeze to install and play on all modern operating systems. Double click on the installer, pick a directory to extract the files, and then double click on the desktop shortcuts to play. It's that easy.
On a side note, I hope there aren't any weird viruses/spyware involved in this "revival."
Anyway...yeah. I have my original CDs and everything, but I don't relish the idea of tracking down all the myriad fixes and workarounds to get them working on Win10.
So enjoy.