I currently have made the stew and my villager doesnt need to breathe now. When I place her in the pond it says she is retriving the gong piece, but that the water is too deep?
The technologies I currently have are
Level 2 Farming
Level 2 Engineering
Level 2 Science
Level 2 Exploration

Also on a different note, now she has eaten from the cauldron, how do I make new reciepes are the cauldron is still full?

Are you sure that you dropped the same villager in the pond that ate the stew without another villager eating it? It only seems to work with the last villager to eat the special stew. Other than that, I don't know.

The cauldron will become empty by itself after a while, but if you don't want to wait, exit the game and restart it.

Thanks I got it working now
If a male and female villager eat the love potion does it mean they will make a baby? I heard it raised parenting skills? I want to raise the skill but with no baby.

You could easily end up with a baby, but not necessarily. Probably the safest method is to make sure the female is over 50 and thus too old for childbearing.

speed kissing them

yes, if not 50+