And he commanded them to be baptized in the name of the Lord. Then they asked him to stay a few days. After Paul laid his hands on them, they received the Holy Spirit. This is similar to the events in Acts 8. That is where Peter and John laid their hands on the Samaritans after they had been baptized in the name of the Lord, so they could receive the Holy Spirit.
Water baptism is the one baptism practiced today by all religious groups claiming to be Christian.
This is the method of the baptism that comes from preaching Jesus. Then Philip opened his mouth, and beginning at this Scripture, preached Jesus to him. Now as they went down the road, they came to some water. So he commanded the chariot to stand still. And both Philip and the eunuch went down into the water, and he baptized him.