Newbie Help with a blog issue

Hi probably had this aload of times, can seem to find a solution at the moment

Running a site with the Innovation+science2 theme on the current version of WP.

I’ve set up all the buttons, but wanna use the main page as a stand alone/static page and want to link to the blog section via the menu

what I’ve done is the following

Created a page in the pages section, linked it to blog.php

then went down to Settings/Reading adjusted the post page to blog.php aswell, since doing that when I click the link on the 1st page nothing appears, and apart from going round in circle fors the past few hours thats as far as I’ve got

can anyone shed some light on this….soz if it is a genuine noob mistake

thanks in advance

Steve