As far as your question about whether skipping water baptism will keep you out of heaven because you just choose not to do it.
Answer: I think the point was more about asking the very personal question of whether a person's heart is totally all into what God wants for them. If a person has not been baptized then that same person should ask them self the question...why not? What is stopping you? We have bathtubs, swimming pools, lakes, rivers, streams everywhere. And of course many churches have their own.
Acts 8:34 The eunuch asked Philip, “Tell me, please, who is the prophet talking about, himself or someone else?” 35 Then Philip began with that very passage of Scripture and told him the good news about Jesus.
36 As they traveled along the road, they came to some water and the eunuch said, “Look, here is water. What can stand in the way of my being baptized?” [37] [c] 38 And he gave orders to stop the chariot. Then both Philip and the eunuch went down into the water and Philip baptized him. 39 When they came up out of the water, the Spirit of the Lord suddenly took Philip away, and the eunuch did not see him again, but went on his way rejoicing. 40 Philip, however, appeared at Azotus and traveled about, preaching the gospel in all the towns until he reached Caesarea.