Jesus left his desciples with the instruction that they should go out into the world and baptise, and there are the examples in the scripture that see them carrying out this instruction.
Of course you will have cases where someone believes on the Lord Jesus in the hospital who is about to die or whatver else it might be why they cant get baptised even though they believe, and those persons will receive mercy from God, just like the sinner on the cross. But aside from that, everyone who repents should get baptised as a sign of their conversion.