How to set language in url on Opencart 3.0.4.0

Hello,
I have a website in two languages: Bulgarian and English.
How can I make it so that when you are in the Bulgarian (default) version the URL is:
example.com
In English version:
example.com/en

Therefore, for categories:
Bulgarian: example.com/category1
English: example.com/en/category1

And so on for all pages

Thank you!

Try this code

viewtopic.php?t=219473