Text Translations – Urgent help would be much appreciated

Hello,

Could someone help me with below? I’m trying to translate my site to Polish language.

– If I update words one by one in Text Translations, does that update language file? so for example if I go change all words through text translations and when if I download language file would that be updated with new words?

If I have to update language file……
– When I download core language file it seems very different to help video tutorial you have done. in my core file I see “premium press” beside all words (see attached). Do I delete word “premium press” or leave it?

– Also help video says do not update “descriptions” array. I can’t see Descriptions in the core file I downloaded today.

Any help would be much appreciated.

Regards
Yohan