Can I somehow set up that registered users can create forums 

You should enable the Dashboard - Manage Forums CAN permission for registered usergroup: 

https://wpforo.com/docs/root/members/usergroups-and-permissions/

I'd also suggest you read this post, you'll find useful information for wpForo Usergroups, Forum Accesses, etc...

https://wpforo.com/community/how-to-and-troubleshooting-2/create-a-forum-that-subscribers-are-unable-to-add-topics-too/#post-19309

And other thing is that "Subscribe to this question" is missing in phrases to translate or in translator plugins (loco translate ex.)

If you can’t find some phrase you can add it using button or navigate to Dashboard > Forums > Dashboard admin page, click on , then try to find and translate the phrase again. 

IMPORTANT: If you did some change in phrases, please don’t forget to delete phrase cache in Dashboard > Forums > Dashboard admin page.

Thanks for your support, but I have few more questions. :D

Can I somehow set up that registered users can create forums and topics?
Because I wanted organic discussion forum where people create everything how they want and moderate how they want.

I have a website about politics in my country so you can understand why I want my users to create everything by themselves because one person cant make so many forums and topics...

And other thing is that "Subscribe to this question" is missing in phrases to translate or in translator plugins (loco translate ex.)

Thank you very much guys and have a nice day.