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Indeed there is! See M-x apropos[1]

[1]https://www.gnu.org/software/emacs/manual/html_node/emacs/Ap...

Also bound to C-h a

There is also C-h d (apropos-documentation)

Check out marginalia[1]. Whenever you press M-x, it will pop up a buffer showing all the commands (with most recent ones on top) along with their keybindings and a brief description of what they do.

Embark[2] is also cool. It will show all the possible commands relevant to where the cursor is at that moment. I bind it to C-c a.

[1] https://github.com/minad/marginalia [2] https://github.com/oantolin/embark

I usually use:

C-h f runs the command describe-function (found in global-map)

If the command is bound it has "It is bound to..."

I'll usually do C-h f (describe-function), then hit tab to make it build a list of all (interactive) functions, and then switch to that buffer and search for whatever I'm interested in.