Newt behaviors?

Hello, I recently bought two baby newts, and I was wondering if they way they are behaving is considered normal. I've done some research before getting them of course, but as I'm new to this hobby I just wanted to make sure if they are healthy or not.

1. One of my newts seems to stay in the water frequently, hanging around by the rocks but never quite getting out of the water. The other newt at first mostly stayed in the water, but now stays on land literally all the time and barely gets in the water with the other one. Which behavior is more normal; staying in the water or staying out of the water?

2. The newt staying out of the water seems to sneeze, and I've seen it yawn? a couple of times. Is it normal for a newt to open it's mouth while out of the water (I've had a turtle that died of respiratory infection, and he constantly opened his mouth to gasp for air while on land)

3. Is it normal for them to float or sink? The one that stays mostly out of the water floats when in the water, while the one in the water sinks.

4. Is it normal for them to constantly swim up to the surface, stick their head out and blow a bubble (to breathe, I guess? Because they have lungs?), or is this considering gasping for air and a respiratory infection?

5. I've never seen any of them really eat (I've been offering frozen bloodworms), but I've seen poop lying around every morning I get up even after cleaning the tank.

6. Just as a question, does anyone know what type of newts these are anyway?

The person who sold them said they were eating and growing quite healthily as he was taking care of them. I currently have them in a 20 gallon tank with a filter (that has very little current), and the water temperature at 66-68F.

I'm sorry for all these questions! I just hope they don't end up dying and I want to keep them as long as possible! Sorry again and thank you!

Hi!
I have such a poor sharpness when looking pics with my phone that I can't tell the species. Probably someone else can do it shortly!
Are you sure they are the same species? Are thy about the same size? Or if it's an aggressive species, that could be the reason. If they are really young, it might be the other one is just not willing to stay in the water yet.
I think floating after staying on land for a longer period is normal, because the skin gets dry. You might even be able to see little air bubbles on the skin but after a while, the skin adjusts to water and swimming comes normal. If a newt stays mostly in water, then it sinks when relaxed but is able to swim in whichever direction it wants. They come up to gasp some air every now and then, I don't remember which was the longest time they can stay in water but I think temperature and such have effect.
You could try to offer some small earth worms with forceps and see if they take it. If they poop, I'd suggest they eat, too

Thank you for answering my questions! I'm not completely sure if they are the same species, however I know the one in the water is slightly bigger and a lot more active than the smaller one that barely moves on land. I suppose this is the reason why the smaller one (only slightly smaller, though) is not willing to go into the water? I will try feeding them live food asap. Thank you!