At this stage your little kiddo is in a position where he understands daily routines like using washrooms without assistance, brushing teeth, etc. When he starts doing these daily routines on his own, he will become more confident and feel more independent.
What you need to know
At this point teaching your child to complete daily routines independently is very important. Initially encourage him to dressed and undressed. By this age, he will understand that for certain daily routines, washrooms are used. Mostly at this age he will try to imitate everything you would do at home. He will easily understand the difference between poop and pee. So he can be asked to communicate and you can guide him to the washroom. Remind him of his daily routines and rules. There are chances that he might forget these things very fast but you can always remind him by asking him questions.
Slowly he will start to understand when he needs to use washroom and he will start using the washroom independently. This is one of the developmental milestone for your little.