Hi DreJr welcome to the forum.
1. No the game will just spawn a bassinet wherever there is enough space for one inside the house. Often it is in the worst possible place lol. You can just go into build mode through Manage World menu and move it to somewhere else if you really want to. Although it makes no difference if you do not visit as that lot will actually never be active.
2. Yes and yes; the noobo will age up into a child after three days if your aging is on normal or turned off.
3. Yes, it just happens off screen as there is no story progression. If you visit the house (thereby turning their lot into an active lot) the NPCs'/ Townies will feed their baby, rock it, change it's diaper etc etc while your sim is there. Your sim will also be able to care for the nooboo while visiting. Often the traits might be a little on the negative side such as insane or mean etc but again you can always change that in CAS using cheats etc once the nooboo is a child or teen even.
If the nooboo is one of your sims then your sim will receive a message letting you know that the nooboo has born once the townie has given birth even if the mother (and nooboo) does not live in your sims household.