How to make the news are displayed in a row?

Just use same HTML is you have h3 in both articles make sure the have same styles/classes.
SO best prepare some HTML you will use, then just change image src attribute and below text

Sorry, I'm not a professional.Please tell me what I need to do step by step

Thank you so much!

Go to first article edit page, swap to HTML mode and copy code, go to other articles past that code and change only src attribute for image and content text , nothing else

2 If all the material in order, but 3 or more ...
your advice does not work

Ok looks better.

First you should limit your images size on blog page, add this to template_css.css:

.blog .items-leading > DIV IMG,
.blog .item IMG
{
max-width:250px;
}

Also you can set #leading to 0 in menu item settings so first does not display different.

Better, but not in row