I have one task to do but i'm not sure where to start. I have to create a content for storing current and historical data for each term in "extaxvoc", the current data will be shown on Search pages for "extaxvoc". I have no idea where to start with it as the task seems strange to me but at the same time i'm completely new to drupal cms overall.
It seems like a little too many extra steps for me. You can use fields in taxonomy terms as well, if you want to store data. You can adjust the search to show terms afterwards, besides nodes(content entities). In any case, if this is mandatory, you can always add an entity reference field in the content type(the one you create for adding content which will store historical data and so on) and just add the needed fields there. Each node will be categorized by the category it references from "extaxvoc".