Q: How do i know what song are on my phone and which are in iCloud

Set Settings > Music > iCloud Music Library = "Off" on your iPhone.  Then you will see only music loaded onto your iPhone.

Asking about playing your music from the iCloud is a completely different question than asking about viewing what songs are on your iPhone.

This should explain the various ways you can play music from iCloud.  There are two different ways to keep music in iCloud: Apple Music, and iTunes Match:

To delete a song, when viewing it in "songs" view, click the three dots on the right that look like "..."

The choose "Delete."

It looks like the link about iCloud Music failed to post above, so here it is:

iCloud Music Library: Understanding differences between Apple Music and iTunes Match - Apple Support

sberman wrote:

 

Set Settings > Music > iCloud Music Library = "Off" on your iPhone.  Then you will see only music loaded onto your iPhone.

I have a fully updated iPhone 6 and that option is not available in my settings. Any idea why?

iinami wrote:

I have a fully updated iPhone 6 and that option is not available in my settings. Any idea why?

Probably because either you are not signed in to iCloud or you have not signed up for either Apple Music or iTunes Match.