Q: How to activate offline option on Apple Music

Hello PKG at Kalkaji,

Thank you for using Apple Support Communities. 

I see that you want to download music from Apple Music to listen to offline. The following article has a section that explains exactly how to do that. Select the center box, "Download music to listen to offline" to take you directly to that section. 

Add music from the Apple Music catalog to your library on your iPhone, iPad, iPod touch, Mac, or PC

Best regards.