If you planning to use custom tabs for all listing types first step is activate tabs;

1-) Go to Options Panel > Listing Detail Page > Page Section Config (Custom Tabs 1-6) and activate custom tabs.

Note: You must activate every tab 1 by 1.

2-) Rename tab as you want and use.

If you planning to use custom tabs per category. Please do everything above and activate all custom tabs. Then;

1-) Go to PF Settings > Advanced Listing Type Config   ( or )   Listing type > Edit > Page Section Config and find your category name.

2-) Enable Advanced Settings and configure custom tabs like above.

IMPORTANT:

1-) If you changing the custom tabs order. Please do not mix the custom tabs number because if you do not enable custom tab from Item Page Detail config. you can not use under Advanced settings.

2-) If you planning to use these tabs under the Frontend Submit Form please check this article.