alternative to sending email using gmail with firebase function

Question

I recently got that email from Google which says that as the beginning of 30.05.2022, we will not be able to use "less secure apps" options anymore.

I'm using this option to sending emails with firebase function combined with nodemailer, as probably a lot of other users do.

So the question that I have is how can we use it after the above date?

If you need an example of how I am using it please let me know in the comment.