Pen tools not working

[Ofnuts]

You pencil is using the "Clipboard image" brush so it depends on the clipboard contents (and from the brush thumbnail they appear to be an empty image). Try the standard round brush (2. Hardness 100) and use 100% opacity

Also, the pencil tool dialog has a lot more options, and some of them would also cause problems, so better show the whole dialog in your screenshots.