In a website I have created a board category and there are 6 posts in total in it. I want to show these post on test page so when I edit the post the changes will show up in test page.
This is the page where I want to show the post: hidden link
This is the example what I'm trying to build like: hidden link
The page at the second link is a static page, where the board members have been added manually, it seems.
And you would like to recreate this, but dynamically, so that the 6 posts with the category "board" will appear in a grid, yes?
For that you can create View and insert the View on the page where you want the board posts to appear.
Your View will query the post type in question (are these standard posts or a custom post type?), and you will add a Query Filter to only show posts with the board category (is it a standard category or a custom taxonomy?).
That will return the required 6 posts.
Then if you want to display them in a grid, you can specify bootstrap grid as the output format when you use the Loop Wizard for the output.