Connecting Bluetooth to your raspberry pi can be really easy if you know what to do.If you have a raspberry pi 400, this can be extremely helpful because there is no built in speaker on it, or if you don’t have a monitor with a speaker.
Since there is no Bluetooth app in the applications menu(or in pi-apps) it can be difficult when starting out. To start turn on your speaker or headphones and make sure they are not paired to anything else. Next go to the right top corner of your screen, right next to your WiFi and volume bar. That is the Bluetooth icon.

click it and a menu will show up. click the option that says, add new device. A window will open that says this

Click on the device that you want to pair and If successful, it’ll tell you to right click on the volume button to add as output. Do that and select your Bluetooth device that you want to pair. If successful your headphones or speaker should say so. If you want to buy a speaker that is specifically made for raspberry pi, check out this one from the pihut. That’s all on connecting Bluetooth.