otherwise you cannot install modules, if you installed Unity outside official Hub,
and now they removed install module direct download link from editor build settings window too..

need to do this setting:
https://forum.unity.com/threads/hub-option-add-modules-disappeard.935219/#post-6118490

• add option toggle for "make hub think that unity was installed from hub" or something
• read file %APPDATA%\UnityHub\editors.json
• replace "manual": true, with "manual": false, and save back