Go to the bookmarks list, make sure you are at root level,
then at the bottom there is a ‘share’ kind of button, tap on it and select Export/import bookmarks,
It will create a .html file that can be exported, this is an universal format so you should be able to import it to Chrome, Firefox etc
Import works the same way, it expects file in the same format
To import, you have to upload the bookmarks html file to your phone then import this file,
Exporting bookmarks saves the bookmarks html file to your drive which you can then upload somewhere else