Is there a license for this project?

[filippopompili]

Hello, I really like this plugin and I think it's very helpful.

I was planning to use it also for work-related code, but I couldn't find an attached license explicitly allowing it. I'm not a legal expert, but according to this website, https://choosealicense.com/no-permission/, "no license" implies "no permission".
If there isn't one, can an open source license such as MIT or similar be added?

Thanks!