Here are some forum threads that may give you some ideas, NorthernerTwo chord songs

seeking two chord songs

two chord songs needed


There are also a LOT of three-chord songs.   Most of Woody Guthrie's songs, many country songs, blues, Gospel and folk ballads -- too many to list. But here are a few easy ones:

Goodnight, Irene
Roll On, Columbia (almost the same melody as "Irene")
This Land Is Your Land
500 Miles
Sixteen Tons
Proud Mary
Four Strong Winds
You Ain't Goin' Nowhere
I'll Fly Away
Keep On The Sunnyside
The Frozen Logger
The Gambler (4 easy chords)
MTA (Wreck Of The Old 97)
Paradise (John Prine)
Last Night I Had The Strangest Dream
I Saw The Light
Margaritaville
Come Back, Paddy Reilly
The Wild Rover
Hobo's Lullaby
Green Rolling Hills Of West Virginia
La Bamba
Cielito Lindo
Red River Valley
Kisses Sweeter Than Wine
On The Wings Of A Dove