Do mammals give birth to a baby mammal in an egg?

Answer 1

No.

Mammals give live birth, like a human baby coming out of of birth canal.

Reptiles lay eggs, like a lizard or Dinosaur.

Correction:

There are two egg-laying mammals. The platypus and the echidna are both egg-laying mammals, or monotremes.They are still classified as mammals because they feed their young on mothers' milk - a characteristic unique to mammals alone.

There are just three known species of egg-laying mammals, or monotremes. They are the platypus and short-beaked echidna (Tachyglossus aculeatus) of Australia, and the long-beaked echidna (Zaglosssus bruijni) of Papua New Guinea. The echidna is sometimes called the spiny anteater, and there are several sub-species of the long-beaked echidna: the Western long-beaked echidna, Sir David's long-beaked echidna and the Eastern long-beaked echidna.