An easy song, if you can play a C7 and an F7 is "Feelin' Alright" by Dave Mason. Most people are familiar with Joe Cocker's version.
Stir it up- Bob Marley
Every Rose Has Its Thorn-Poison
In The Summertime-Jerry Mungo
Me and Bobby McGee-Janis Joplin
You Can't Always Get What You Want-Rolling Stones
Angel From Montgomery-John Prine
I Remember You-Skid Row
I Can See Clearly Now-Jimmy Cliff
Run Around-Blues Traveler
There you go. You like all music so I gave you some Reggae, Alternative, 80's ballad, 60's feel good, 60's rock, Psychedelic Rock, Grunge and some Pop.
A little tip. GET A METRONOME! It will help you immensely. Play these songs at a slower tempo to begin with and get used to the chord changes. Also, don't be discouraged about trying to sing and play at the same time. It took me forever. So frustrating!!! and PRACTICE, PRACTICE, PRACTICE. Build some callouses.
Peace in. Peace out.