Before you get any wrong conceptions, No I am not launching another scam.
Not at all, so far as you are asking no one to invest or pay money for the first worskshop, many people will be interested in being a part of it.
If you do not have sufficient capital to get a space maybe a hall to accommodate people that will be interested, you can choose to leverage on technology as well and hold your workshop or seminar or whatever you like to call it online (A closed group on telegram maybe).
After making that decision on the venue at the offline or online the next thing is to search for another speaker that will assist you. Someone who is particularly knowledgeable in bitcoin as well.
Pick a date that is not too close, so you can have enough time for the next thing which is publicity.
Invest heavily in publicity because publicity is what will determine if your workshop will will turn out successful or not. evaluate the best way to reach out to people around you and leverage on it because you need people to come.