S.H.
How old is your daughter?
Next, depending on how old, kids are often not yet able, nor have the coordination/dexterity to pull down their own pants/pull-ups/underwear. So you need to help them.
Even 3 year olds need help or with even basic dressing/undressing themselves.
Potty training occurs in stages and is a process. It also has to do with the myelin development of the nerves.
Keep in mind, that dryness during night-time and naps is a WHOLE SEPARATE process & ability.. and will not occur yet. Night-time dryness... can even take until 7 years old, which is normal. And accidents may still occur. And per our Pediatrician.
One step at a time.
For night-time... once she is actually at that stage, a waterproof bed-pad is very good to have... put it right under her, and it makes clean up much easier. I have about 4 that I change out and launder as needed, if my kids wet the bed at night or during naps.
Also useful, is a car potty. For times you are in a car and there is no bathroom in sight or the child cannot hold it or wait until you reach your destination. On www.amazon.com just put in the search words "on the go potty". The car potty, has been a literal life saver for us and our kids. Our friends have these car potty's too. Very useful.
Potty training is in 3-4 stages:
1) daytime peeing "mastery" and in the toilet, being able to tell you and pull down their own pants.
2) pooping in toilet and mastery of it.
3) night-time/nap time dryness.
Also, their ability to "hold" it until they reach the bathroom and them telling you before they have to go pee/poop. AND their gradual ability to actually wipe themselves... which will take until she gets much older.
These stages do NOT occur at the same time, nor should be expected to occur at the same time.
Potty training takes time to completely "master" it for the child, and it will take longer if the child is not ready.
Also, regression or mistakes and accidents WILL happen. Which is completely normal.
Well sorry for rambling and the extra suggestions.
But yes, pooping in the toilet, is usually something a child will do, in time. Not right away. Or they will, then won't. Main thing is, don't pressure them or they will get constipated, or "withhold" their poop, even if they have to go. My daughter, even if we did not pressure her, got constipated. We had to see a Pediatric Gastroenterologist and he said, potty training toddlers often go through this... but constipation is difficult to remedy, since going poop, while constipated and if the child withholds it, it will hurt. Creating a vicious cycle. He recommends, just waiting until the child is ready and comfortable to poop in a toilet. That day will come, maybe just not yet. Nothing wrong, with pooping in a diaper if that is only where she will go, right now. In time, she will go on a toilet. Better to let her go there, than to have her constipated and it being a battle. Lots of kids, will not yet, poop in a toilet right away.
All the best,
Susan