I really need some advice here

Hi, I need some suggestion here so i have 4+ yoe in the industry I still consider myself at learning stage. I have been doing almost the same task for good sometime. I am planning to resign without any offer due to some issues I want to take a break and then continue working after few days possibly after a month however my closest friend have a start up and requires a lead I have got an offer to work with my friend for sometime this does sound exciting and a learning opportunity but here's a thing I'm not a right mental state i.e., I have been experiencing anxiety for sometime now and due to which I have decided to take a break although I want to take this opportunity I'm scared what if I don't deliver things Secondly it's not official hiring in an unofficial way I have been approached to manage and lead the team something I haven't done Thirdly even if I take up I'm afraid it might arise sone conflicts and we haven't spoken anything on terms of the money although my friend mentioned I will be paid but Didn't feel negotiating and I'm afraid if I don't fulfil the expectation. it might cause a damage to our friendship