This will depend on your current circumstances. In some cases the person that referred you to a centre will pay for the cost of you being there.
In other cases a court order might outline who is to pay for the cost of using a child contact centre.
Sometimes, one parent will cover the entire cost of this.
Sometimes it might be possible to make an agreement with the other parent where the cost is shared.
Why not speak to the centre or the person who referred you to see what might be possible?