Orientation cube: In the 3D view, top right, you can see an Orientation cube.

Rotate the view by clicking on an edge, corner or face to fetch it into the foreground. Repeated clicking on a face rotates the part around the perpendicular on the face.

When clicking on short descriptions on all functions can be found.

When clicking on a button top left, further buttons (functions) are displayed.

Cut: Click on the axis, you want to use for moving the cut.

Measure functions:

Switch Projection mode: Perspective on / off