Hi, you should add an option so that if the user types the title/description in capital letters, it will be converted to lowercase when published, with the first letter capitalized.

You can use ucwords function in your theme.

Are you planning to add it to the epsilon theme? Could you tell me which file I should modify and how to implement it?

No plans.
item.php, loop-single.php

Is there any way to change it globally? Because modifying item.php and loop-single.php only changes the title, but not the breadcrumbs or the metadata. Is there any way to modify everything at once without modifying it individually? I use the "ucwords(strtolower(osc_item_title()))" function.

@Alej
Ideal solution for you is to update database data and after publish/edit of new items capitalize based on your preference.