Children learn to tell the time at different stages. I have attached a selection of different resources your child may wish to use (or select from), alternatively, taking an analogue clock off the wall and talking through it together is very effective!
The aim is that children can learn to tell the time to 5-minute intervals. e,g, 5 past 5, 10 to 1 etc! Some children will need to recap o'clock, quarter and half past first!