Entering WP link into facebook manually displays….

Hello, I am VERY new to WP and for the 3 days total I have spent on it I think that I have done fairly well. I have a working site set up. (www.djchiments.com)

A little background. I have installed WP to /wordpress
I have redirected my domain to that folder so typing https://www.djchiments.com into my browser auto directs to https://www.djchiments.com/wordpress

Now I have plugins installed to auto post my updates to my facebook feeds and whatever. When I manually enter my URL into the facebook wall post box it auto populates the URL into a link, summary, and thumbnail if present. Great, normal.

However it summarizes the FIRST post of my blog. Not Good.

If you are unsure what I am talking about go to your facebook and share this link: https://www.djchiments.com You will see if summarizes my first post.

My Question is this: How do I (or is it even possible) make it so that when I just type in my main URL it shows the title, sub title and some generic description of my WP and NOT the 1st post?

Is there some code I must enter? In the header perhaps? I know this is a small tweak but this would mean a lot to gain some assistance.

Thanks!