Template recreation hint

Please I need help as to how to change the Event submission template to the one I had in Joomla 2.5 (eventlist).
I do not know how to remove all those unneeded tabs and forms.

Here is what I had before:

what do you have now, please add a printscreen of that too. Because it depends on template.
Or are you on a clean joomla 3.6.2 with only official extensions, templates, plugins.
If not try to find your problems eg with firefox and firebug.
In other language it depends sometimes of the length of the words in a language.

I had a clean J3.6.2 installation, only with two extensions and a special yootheme template (gsg.si).
The only problem that I experience is the calendar tooltip which was working fine for two days, now it appears totally on the left, without me changing anything.

But now my kind request: as you can see in the image I only need to cancel or move things, fileds etc. Before in eventlist I could do it alone, now I can not. There are so many files, I do not know where to start ...
Also the language file has around 5 language strings for the same thing. So it is hard to translate into slovenian. I wanted to contribute to tranlation, but still no one accepted slovenian at transifex, or I do not know hot to do it. Sorry for many things that bug me, but I guess you are the right person to talk to. Main problem now is how to make a simple layout for publishing events.
Would be awsome if you could somehow help me to do at least as it was before.

Hi there urednik,

I'm stepping in here, because translations are my responsibility.
I noticed you sent a request on Transifex on August 24. I just got back from holiday today, so did not yet have the chance to respond....

..but I just sent you a message on Transifex

I answered you there, thanks for contact Ernst. Hopefully I get to the template modification soon

Hi,
at the moment we discuss some changings in the order of eventedit
I hope you are experienced with ftp and using template overrides.
then for the frontend you can at least move the needed fields to the first tab and move the unneeded fields to the other tab.
The first tab you'll find in the site views/eventedit/tmpl/edit.php. At the end of this file there are links to the other tabs.
EDIT:
But you want to hide so much fields, we never will adapt this only for one person. So it's up to you making such adaptions.
You know now the place for frontend.