I want to know the next steps I will not promote

I have a florida llc and my EIN and also bank account with mercury but I will move to San Francisco with a Co founder so that we can build it together. What documents will I need for my start up to be official and which ones will my co founder have to sign? and how much would each of them cost? For the documents is it a lawyer who has to draft them or is there a website where I can do all this? I already have sketches and and know how the mechanism should work. We will use personal pre seed funding to creat