Customize custom posts

Hello!

I have custom posts on my wordpress and i would like to customize them but i have no idea how. I would for an example fix so it would be easy when i create a new post in my custom posts to add a image that is connected to this post and will be shown at the top of the post when it’s published. I would also like to have a input field where i can add a website link that is attached to the post and will be shown at the bottom of the post when it is published.

Here is a mockup how i would like for it to look like.

View post on imgur.com

I´m so grateful for tips and instructions, thank you!