How do I fix my Mac's Bluetooth keyboard and mouse issues?

So here's the scenario : MacMini v 15.3

iPhone 14 v 18.4.1

iPad 9 th gen. v 18.4

I have a Mac with Bluetooth enabled keyboard & mouse . In the room next to it , I'm trying to pair an iPhone with a fitness device .

Hardware is my weakness so I have to ask … could the phone or the fitness device have paired with the Mac ?

⌨️ I realized that the keyboard & mouse were malfunctioning around the time of the 15.3 update but I don't recall when fitness device may have been paired . I unpaired it shortly before writing this post , I'm guessing that I saw it on iOS a few times over the last three months ?

🖱️ I just bought a new mouse for a laptop , haven't opened it yet … could I use it to navigate troubleshooting the Mac Bluetooth problem without the keyboard working ?

🖥️ 📱 💻

[Re-Titled by Moderator]