REQUEST/Question for addon

[Krayyfish]

So this addon may already exist and if it does could someone link it to me. But is there an addon that tracks a bosses hp % that you could configure to certain builds where at a certain percent you can set it to show an alert to drop certain skills and when to start execute? If there is no such thing is there any way someone would be willing to try and create it? I feel like newer players and players who want to get into more endgame content could use this as a tool to help them remember which skills to drop in content. I especially have very bad adhd and forget which skills to drop when it comes down to it so if anyone could help out that would be great.