Sorry to hear of the issue.
Summary judgment is where the court thinks you have no real prospect of successfully defending the claim.
It means there is no need to attend a full hearing but it also means your defence is so weak as to have no merit and the claimant therefore wins.
You mention there is a hearing on 5th September and I presume the claimant has applies for summary judgment against you.
As you have yet to file a defence I struggle to understand why - as normally you would have already filed a defence and the claimant thinks the defence has no merit - then they apply to the court. Or, the court thinks the defence has no merit and grants summary judgment, either way.
I don't know if you have missed the deadline to submit your defence. It sounds like you have. You say you have to submit your defence within the next two days - again, I don't know if you have a court order to say you have to do this or you are doing this on your own back.
But as I say, normally you will have already replied to the claim and the claimant then applies for summary judgment so I remain confused on this point and perhaps you can clarify.
In the meantime, to answer your question - you say you want to get the hearing adjourned (it's not until 5th September which is over a month off?) then you will need to make a formal application on form N244 (https://www.gov.uk/government/publications/form-n244-application-notice) and pay the court fee which you can do by telephone once you send your form to the court.
As for a defence, it needs to comply with the CPR rules (https://www.justice.gov.uk/courts/procedure-rules/civil/rules/part16#16.5
) and it looks like the attached - it must be in numbered paragraphs and address the allegations the claimant has made. It then needs to be signed (the statement of truth).