Galatians 3:19-20
Paul is referencing God giving Moses the 10 Commandments on stone tablets, I think. I tried to cross reference but I don’t see the verses that say actual angels were present at that moment. In Exodus 23:20-21, however, is God telling Israel an angel will go with them to protect and lead them on their journey. (I didn’t include it on our list.)
I’m sure God used angels more than Moses wrote about during their Exodus from Egypt and into the promised land. He was able to speak directly to the LORD and be in His presence. I’m sure he saw angels and knew what they were too. Maybe that’s something we can talk to him about when we get to Heaven.