Yeah, that’s a heresy they were teaching in my Catholic school that caused me to leave the Church because I thought that meant I could go out and do whatever I wanted and just choose not to go to Hell after I die.
We “choose hell” insofar as while we are alive we reject God by committing mortal sins. If we die in the state of mortal sin (all it takes is one unconfessed mortal sin for us to go to Hell) we go to Hell. After we die, that’s it. After we die and see God, we don’t decide whether or not we want to reject God and go to Hell for eternity rather than choose to spend eternity with God in Heaven, or decide “Hmm, I don’t think I’m ready for Heavenly Bliss with God. I think I’ll go spend time burning and suffering in Purgatory first.” After the Fall of Adam and Eve, we’re pretty stupid. It’s illogical to suggest that we decide after we die where we want to go, or that we’re the ones who judge ourselves. It’s pretty pointless for a person to judge the state of his or her own soul when he or she is blind and stupid from sin.
When we die, we are judged by God immediately. He reveals to us intellectually every action, thought, etc that we committed while were we alive, whether or not it was sinful, and to the degree it was sinful.
If we die in the state of mortal sin, God pronounces His judgment on us and we spend eternity in Hell.
If we die in the state of sanctifying grace, but have not made reparation for the temporal effects of our sins, or we still have imperfections, God sends us to Purgatory to be purified.
If we die in the state of sanctifying grace, and are free of all temporal punishment from our sins (or we die right after being baptized before we have a chance to sin), and have already been purified of our imperfections, or we die a martyr, we go straight to Heaven.