The extension Command Explorer is great for this: https://marketplace.visualstudio.com/items?itemName=MadsKristensen.CommandExplorer

As the listing describes:

• Open the Command Explorer window (View > Other Windows > Command Explorer)
• Toggle on "Inspect mode" to point out where in the UI the action is located
• Get to the right place in the UI, then Ctrl+Shift+Left Click to select the command and have it populated in the command list