QuoteIt looks like you want the community to program the whole module for you.
As I've said - i just needed a php code for returning repeatable RTE field. Where did I ask for all the code? Before asking you guys on forum, I already had created database, extended default category formbuilder and JS with ajax request. I thought there would be some proper way to return input, rather than hardcoding it in tpl file (or twig file).
Anyway, I have finished my module, I have added buttons to delete each row. Everything works pretty well.
And btw The published code of the first person did not work so I didn't even want to ask or force to correct it because this would be the reaction 'you want them to do for you'
I think we can close the topic. Thank you guys for helping me out 
I appreciate it