https and http working from same public ip address

Question

First this is my first post so forgive me if I don't explain this correctly or I post something without enough info. I have 2 separate physical machines , one running a wordpress site, the other one running a iRedMail mail server. They both use nginx as the server engine. This is a hobby just to learn wordpress and mail servers. I run these out of my home on a regular fiber internet service. So I have a dynamic public ip that doesn't change often. Also I only have one public ip address. What I am having problems with is I want to in a browser type www.dccathome.com and get the wordpress site but what happens is when I do that from the internet my iredmail site redirects it to https://www.dccathome.com/mail Since this is a hobby and I am not running a business I don't want to have to pay for business internet an multiple ip's unless there is no way to do this with my setup. iRedMail wasn't much support so that is why I am here. Thanks in advance Dan