Can a member’s post be set to notify everyone who posted in certain category

I have created a test site to see if I can make member posts notify other members who have posted in a specific category when a member posts a blog post. I need the member to be able to select certain categories and notify the users who posted in those categories. In other words, user A posts about his band. User B posts about needing to hire a band, selecting the “band” category. User A then receives a notification about user
B’s post. How can I do this?

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