I need help with installing CDLC, so I could learned to play some song I like. I don't have the steam version.

https://customsforge.com/index.php?/guidelines/;

No piracy, no mentioning piracy-related sites, no crack discussion.

You are risking post deletion, account suspension / ban while putting this site at risk.

No one here will be able to help you, see the site guidelines. If you wish to use this site, and CDLC, you will have to find a legit copy / Steam Key and redeem it while avoiding scammers, cut throats, scalpers, and already redeemed / used keys.

Best of luck.