A sus2
The A sus2 chord consists of the A (Perfect unison), B (Major second) and E (Perfect fifth) notes.

How to play the A sus2 chord
- Find A (Root) on the piano keyboard
- Add B (Major second) — 2 semitones above A
- Add E (Perfect fifth) — 7 semitones above A
- Press all 3 notes simultaneously to sound the A sus2 chord