I dunno if anyones posted something asking the same question, and if so Im sorry but what are some songs I should learn to practice singing while playing?
Sometimes I put a rubberband around my nuts and practice my Coheed & Cambria vocals

"Good eye, sniper
I shoot, you run"
Mordred's Song by Blind Guardian, it has some pretty easy rythm parts and some parts where Marcus sings in the chorus...
lets see...the songs that helped me learn to sing and play at the same time were... Slide by the Goo Goo Dolls, Times Like These by Foo Fighters, and i know there's more but i forget the rest.
Genocidal club #3. i was promised respect....

Cuando moría; Vi todo cerca de mí, todo lejos de mí, y todo adentro de mí. El cielo fue abierto, y en oblivio, me olvidé.
Glycerine - Bush
Wonderwall - Oasis
Then just keep practicing with progressively more complex rhythms.