Welcome to SW forums Taras

Where you looking to change the language. SW will use the language you specified during installation. If you looking to use English (thought you have installed a differnt language), then go to Tools > Options > General and select the following two options:

1. Use English language menus. (Available  if you specified another language during installation and the regional options  in the Windows Control Panel are set to  that language).

You must exit and re-start SolidWorks for this change to take place.

2. Use  English language feature and file names. (Displays feature names in the  FeatureManager design tree and automatically created file names in English.  Existing feature and file names in a foreign language do not update when you  select this option).

This option is available when Use English  language menus is cleared, you are running the SolidWorks software on a  foreign language operating system, and you installed SolidWorks for that foreign  language.