Help figuring out a part of a song

[u/Seriously_Stiff]

So I’m learning Need to Change by Landon Tewers ive got everything down except one part at the beginning of attached video he hits chord 6 3 times first while pushing fret 3 then 2 then back to 3 at the end he does the same hits the same melody but different chords and or frets can anyone please help me figure out what he’s doing there