Welcome, and enjoy more good ideas.
Use the pencil to make marks-hatching, cross hatching, weaves, curls, whirleys, dots, shades, dark to light, drawings with just the pencil, use the side of the pencil as well as the point, use the eraser as a drawing tool, too, blend/smear with finger or tissue, etc.
You might find some ideas here:
https://sibleyfineart.com/tutorial--draw-trees.htm
Draw items in the room, on your table, your toes, fingers, scribble, sketch, add shades and shadows...