On an Apache server this is accomplished using an .htaccess file in the server directory of the 'second blog'.  There may already be an .htaccess file present in that location...  if so it's fine to simply edit the existing one (carefully!)

You need to add the following single line to your .htaccess file:

DirectoryIndex name_of_page_showing_blog_article_list

...where the name of the page includes the file extension.  I'll try and explain further...

Under normal circumstances an Apache server will usually look for a file called index or home or similar, so by default the DirectoryIndex is set as follows:

DirectoryIndex index.html  (for example)

By defining the page which you want to serve after the DirectoryIndex instruction, you can force the server to serve that page instead of the index page...  so set it to be the blog article page.

If you need to create and upload an .htaccess file from scratch then you can use the following instructions as a guide:

How to create an .htaccess file and what it can be used for?

If you're uncertain about working with files directly on the server then I am sure your webhost will be only too happy to help.  It's best to ask for assistance if in doubt, as errors in an .htaccess file can temporarily 'break' your website until those errors have been resolved.  But if you are working with a brand new .htaccess file then you can have a little more confidence:  if your website doesn't work as a result, simply delete the entire file from the server and you will be back to where you started.