Drupal 8.x

In my twig template for Events I currently have date listed 3 ways:

When trying new themes, you must recreate blocks (with new machine names), is there no way to reuse what is currently created from the previous theme?

Hello,
I look after a multilingual site (default language: German, additionally: English and Italian), running Drupal 8.6.13 under Debian 9,/PHP 7.3. Within the Breadcrumbs block (Bartik-subtheme) I want to display the titles of visited pages. This works fine in the German language version, but does not show up in the other languages. I have neither restricted the languages nor the content types in the block definition. The "Easy Breadcrumbs" module is enabled and at version 8.x-1.8.
Any ideas?
Regards 
H. Stoellinger

Hello,

I'd like to move from one webspace to another while also switching from v7 to v8.

My question, is the source changed or only data read and imported into the v8?

How does one extend a block from one column to two. What might the best layout option be for this?

Hello, I am something new in Drupal 8 and I have a field in users that is called branch office and is filled with the taxonomy branches, I can en discharge a user with several or a branch office, then I have a content that also has the branch field and shows me all the branch taxonomies, which I want is that by adding a content just show me the ones that I select when I discharge the user. Does anyone have any idea how it's done?