problems with layout blog startpage

Dear all,

I have problems with the starting page of my blog. So I entered the link directly to the blog.

The questions are: Why is the background color for date and author in light green and how can I change this to gray?

Next problem: I want to add pictures to the blog starting page. Pls see screenshots here.

1.) I want to add a picture. https://ibb.co/5krDsvb

2.) I see now upload function: https://ibb.co/GTs8jnY

3.) I try to move some random pic from a folder on my computer there. Result: Everywhere the same pic.https://ibb.co/fMFNcxk

So how can I add different pictures for each article? So for each article another picture?

How can I add more green background space between blog and footer?

Because now it looks like this: https://ibb.co/FzjFWVF

On the blog articles pages itselves how do I get more space between tags and the green background?

now it looks like this: https://ibb.co/PmbK6mc

thank you so much in advance for your help!

BR Angelika

The page I need help with: [log in to see the link]