Your very first song using chords, well only one chord, Em (E minor) This is a really easy chord for guitar, so we will start here. The Em chord has 3 notes: Mi-Sol-Si.
The same Em chord in another song, notice how the rhythm is different but still you can play it, because you know this chord.
You can play as many songs as you like, as long as they have only one chord, the Em, because you know this chord.
Just follow the rhythm of the song and play Em. Everytime you play, try to make a clear sound. For piano use two hands.
Another song using Em, by now you should know this chord really well
Time to learn a new chord, Am (A minor) The little "m" means minor. Only 3 notes in this chord. Am has 3 notes: La-Do-Mi. If you don't see a chord on top of the measure, don't play anything
Now you know two chords, let's change from one to another, this may take a little more practice. Do not play the next song, until you can play this one really well.
One more song to practice the Am chord. Follow the rhythm of the song all the time, and play on time with the music.
A Japaneese style song with only two chords, Am and Em. Most of this kind of music you can use two chords.
There are not many soongs using Am, and Em. These are just songs I made for you to practice.