Sure Veanne! Its really easy, as they are habitual by nature. They usually pee and poo in one same spot.
When you first bring a rabbit home, prepare a litter box for it, and to help you rrabbit learn, put its pellets & hay near or in the box (depends on how big the box is). Normally, they poo while they're eating. So, if you arrange their space such that they can sit in their litter box while eating, they will soon get used to poo-ing in the litter box.
If they pee outside of the litter box, soak the pee in tissue and leave the tissue in the box so that they recognise their scent. Clean the spot where they peed with white vinegar, that will help to remove any scent to avoid them going back there to pee.
Some rabbits can be more stubborn and choose to pee elsewhere. if your rabbit insists on peeing elsewhere, move the litter box to that area. Sometimes we have to accommodate them
its recommended to limit your rabbit's space to a smaller area when you begin litter training (although i broke this rule with my rabbits :p but they still learnt very fast). Once they have learnt, then you may increase the size of their area. If the area is big, you may need to prepare 1 or more extra litter boxes. Otherwise, they may not be able to make it back to their usual litter box in time hehe
so far, i only have 1 litter box for each rabbit. seems to be enough for them.