Bath time is a good time because he is undressed already. The running bath water sometimes helps the process. Once he has success with bath time, add other times like the first thing in the morning. Then add regular reminders to go try pee pee, not closer than two hours apart. After meals and before going outside are good times as they involve another activity.
Boys generally train later than girls.
Some experts feel that one reason may be that boys are first taught to stand when urinating. The general recommendation is for boys to begin by sitting initially and then move on to standing once they are having some success with bowel movements. If they are standing most of the time they may withhold stool. Hand washing and wiping Hand washing is often part of the fun of toilet training for children and a routine that is important to establish early. Wiping is something that comes gradually but an important skill to learn.