Training pants which are also known as Pull Ups which is a brand name are just pull up type diapers.
The Pull Ups or training pants are not as absorbent as regular baby diapers are such as Pampers, Huggies, Gentle Steps or other diapers but they do catch some pee if the child does not make it to the toilet in time.
However during potty training it's best to just keep the child in a regular disposable diaper and remind them to use the toilet.
Take the child to the toilet when you think the child is needing to use the toilet to pee or poop and remove the diaper and then put the diaper back on the child if it's clean.
Remind the child that they are wearing the diaper just in case but they should go to the toilet when needed.
Eventually once the child can keep the diaper dry or at least partly dry for a few hours in the day then they can go to wearing regular underwear.
Or you can just put the child in underwear and then deal with the pee and poop messes that happens.