making posts go to certain pages

You cannot assign pages to categories, only posts. Make sure you understand the differences.

https://en.support.wordpress.com/post-vs-page/

+1 to what ambrosite explained.

If it’s a matter of navigation look at
How to easily display links to both Pages and Categories in the blog navigation header?

If it’s more than just navigation, then look at the List category posts plugin or consider the Page of Posts example in the Pages article.

for some reason it wont install that above plug in

If necessary, manually install it.

See Managing Plugins for more info.

I’ve tried that but they arent showing up for some reason

It says its installed when I try to install it from the wordpress plugin page but its not showing in my plug ins page

Some host situations may need you to set your file permissions and make your wp-content, wp-content/plugins, wp-content/themes folders to 777. Sometimes the same needs to happen to wp-content/uploads.

I changed all them, ill see what happens

still wont install ?? I dont get it.