You can't lose salvation Anon, that is a Calvinist belief. Romans 11.29 says otherwise.
"For the gifts and calling of God are without repentance."
This means it is irrevocable. It doesn't mean you aren't going to get some kind of punishment though. According to Matthew 16:27 Christ will "and then he shall reward every man according to his works."
Also note, some variants of Christianity bypass salvation; If you have never actually asked Jesus for your salvation, you can do so now - https://billygraham.org/answer/how-do-i-receive-gods-salvation/
Also, if you have never been baptized through full immersion, you will need to find either a Church that will do it or at least another Christian and a body of water, even a pool will do. Drops of water on your forehead aren't the proper ritual.