If you’re looking to restrict access to entire pages/posts then I would suggest searching for “restricting wordpress content based on user role”. That’s really a larger WP question what there are a lot of plugins and tutorials on how to deal with this.
Allowing users to edit content on the front end of the site can be done using acf_form() https://www.advancedcustomfields.com/resources/acf_form/
If you want to just restrict specific fields and your using ACF5 you can give this a try https://wordpress.org/plugins/user-role-field-setting-for-acf/
