Hi @brown7477, welcome to Caddy.
I understand it’s all a bit overwhelming. Luckily there are some really dedicted people here to help. I know from experience 
For now I can recommend that you install Caddy 2.3 Caddy 1.x is no longer supported.
Next step will be providing us some more info. From the info you have given so far I don’t understand what setup you are trying to create. You are trying to get a https connection to Owncast but through what?
What configuration have you tried so far?
Perhaps you are trying something that is explained here