in / on the bed

English as a Second Language English Vocabulary, Grammar and Idioms
1

When I ask my baby boy to go and lie on the bed in order to drink his milk before I put him to sleep, is it OK to say:
“Go in / on the bed?” (it doesn’t seem correct)
or should I say:
Go and lie on the bed!"

Thank you very much!

2

Go to bed.

Tom

3

Thank you for answer.
‘Go to bed’ as in ‘Go to sleep’?
This is not what I meant. Before putting him to sleep, we spend some time drinking his milk and watching cartoons for a while so that is why I’m suggesting him is better to lie down to do that than stand or sit. That is why I tell him him: " Go and lie on the bed!. Is it correct?
Thank you again for your answer.

4

Also
Go and lie down.
Lie down on the bed.
Go and lie down on the bed.

If he is older, and sits up to drink milk, then:
Go and sit (down) on the bed.
Sit (down) on the bed.