Lyric discussion by missworld77 

Cover art for C Moon lyrics by Paul McCartney

This song's cute. I think it's about being young and feeling misunderstood. It's kind of saying you can't ignore your dreams.

It will be L7 and I'd never get to heaven If I filled my head with glue What's it all to you?

So, about this part, L7 (as someone already pointed out) is British slang meaning square and C Moon's the opposite of that. I think he's saying 'my life could be really boring and I could follow all the rules but I would never accomplish anything unless I let myself be who I am.'