Display post different after specific number of posts?

either add a counter to the loop, and use a conditonal statement;
or use the $wp_query->current_post variable with a conditional statement.

for ‘only on index page’ look into https://codex.www.ads-software.com/Conditional_Tags

alchymyth, is it possible to get som example code? I’m struggling, only get it to work for a specific post number, not for (example) post 9 to 9999.

is it possible to get som example code?

please

tis will depend on the level of ‘style/display posts different’ and on your existing code.

very general example:

<?php if( $wp_query->current_post < 9 ) : ?>
show post in one way
<?php else : ?>
show posts in a differnt way
<?php endif; ?>

this could be as simple just within the post div to set a css class for the two groups of posts, or wrapping the full output section so you can have a total diffrent html and oputput structure.

needs to be within the loop.

Thank you alchymyth you are very helpful, that did the trick!