I have tried ticking comments and discussion but still don't seem to have a comments box. Even went through and ticked individually for each post. Help!
Try temporarily switching to another theme(f.ex. TwentySixteen) and see if the comment box shows with that theme activated.
If so, the theme you're using might not have included commenting in the first place. Then you should(preferably) make a child theme, and add the following code below the content code:
<?php comments_template(); ?>
Usually inside single.php