I'm not sure I'm creating a Custom Post Type correctly?

I'm trying to create a custom post in place of the standard blog post. I have an online program plugin, similar to your coursepress, and it uses blogs to present the pages. It currently doesn't look good as the standard blog page.

My intention is to create posts to present the programs more coherent with the look and feel of my site.

One thing i would like is to, and I can see it as in setting tab, is to use my custom post as the default post but isn;t seemly working.

Can you help? I would to understand how to present custom post instead of blog post.

Many thanks