They create their shell during development, while inside the egg. SO they have an "immature" shell at hatching.
egg and custard
Mommy and daddy snails.
Grown up snails
Snails are of the phylum Mollusca.
There are over a hundred snails!
Some of species born alive, but most of them are born hatched.
No, snails do not leave their shell to burrow.
A fish egg has baby fish in it, a snail egg has baby snails in it!
about 2-3weeks
Some species of snail certainly will if they get the chance.
It will most likely be Egg Clutches.
Baby snails do not find empty shells, in fact, they are born with clear, soft shells. The shells harden as the snail consumes calcium and they start with the egg shell they hatched from. The shell grows with the snail and the inner circle of the shell is the shell the snail was born with.