A screen capture of my Lightroom Classic - the top level tool I use to develop my Raw photos.

It also shows the menu item Lightroom calls Tools.

The Tool Strip (or Tool Strip Bar): This is the narrow row directly under the histogram featuring the icons for Edit (Sliders), Crop, Healing (Eraser), Red Eye, Masking (Circle), and Sensor Dust/Clone. In Lightroom terminology, these are the actual local adjustment Tools.

And I have opened up the details of the Masking tool.