How can I win in the superior court if all I have is a signed agreement and texts?

Hi I am in a situation someone owes me 80k and I don’t want to deal with them anymore,
How can I win in the superior court in Ontario Canada if I have a signed agreement and texts.
I have a couple banks where I had to close them so I don’t think I can get the money records.
I am on Odsp and am also looking for a lawyer to help me with my case if someone could give me a few pointers to the right direction it would be much appreciated:)