OK, here's a simple and convenient thing for you. If you enable Spotlight, then ⌘-Spacebar tapped gets you to the simple search bar. I use it all the time on the Mac to find things. You enable this with Settings ↠ Spotlight and on MacOS Big Sur on the lower left is a Keyboard Shortcuts button. Or, you can go to Settings ↠ Keyboard ↠ Spotlight and turn on Show Spotlight search and turn on the shortcut. (I personally don't find the Show Finder search windows that useful since Spotlight is so fast).

But if you enable it, you can also long-press ⌘-Space, yes just hold it down, and eventually Siri will pop up on your screen if you have an older MacBook. That is really convenient for doing things like "Play Music" and you don't need to find it at all. Or "Open System Preferences" works too. The Big Sur options in Settings ↠ Siri are to:

• Listen for "Hey Siri" on headphones. Which I actually found doesn't seem to work on Non-Apple headphones like my Sony WH-1000MX3
• All Siri when locked
• Keyboard Shortcut set to Hold Command Space
• Voice Feedback: set to On

The trick (or maybe bug) is that you have to hold that key sequence for a good second before Siri pops up in Big Sur at the upper left and you hear the chime.

And while we are at it, you might as well turn on these other useful Shortcuts:

1. In System Preferences > Keyboard > Shortcuts > Input Sources, if you have multiple languages (I have Chinese and English), the ⌃-Space or Ctrl-Space switches inputs.
2. In System Preferences > Input Sources, enable Use the Caps Lock key to switch to and from U.S.
3. In System Preferences > Keyboard > Dictation, turn on Dictation and enable the shortcut, Press Control Key Twice, so that when you kit the control key twice, then in any text field like this on you can try the built in you can try the built-in text to speech which actually works pretty well. And then when you are done hit the ctrl key twice again. As a test I'm actually using the dictation feature right now to write this sentence. Actually it is pretty accurate.

And the final key not to forget is Ctrl-Cmd-Space which gives you the emoji input menu.