If you have a forthwith CCJ you can apply (no fee) by letter for a redetermination with a hearing. This will result in the case being transferred to your local Court. If there is to be a hearing anyway to decide whether there should be a final charging order, you should ask for both to be heard together. You should also ask that, if the charging order is made final, it should include a provision that an order for sale cannot be made so long as you pay whatever monthly instalments the Court decides.
You have to provide income & expenditure details and make an instalment payment offer. Take to Court proof of income - pay slips, benefit letters etc. - & of all major outgoings such as rent or mortgage, utility bills etc. You may be asked for them, but it is not certain.
I suggest you get more details about all this, either from your local Court office or local CAB.