How In the world do you do pizz.

see: https://musescore.org/en/node/50196

click on the first note of a section where you want the notes to be played pizz. click ctrl + t or go the add menu and select "add staff text". type in pizz. click in an open space after typing pizz, then select the text by clicking on it again, right click the text and select "staff text properties" from the menu. You'll see a pop up screen that has voice number buttons and a "normal" next to the numbers for selection whether you want the voice to sound normal (arco) or pizz. Select voice one, (assuming you only have one line of notes written on that staff to be played by a singular instrument rather than multiples melody lines on the same staff), then go to the normal scroll thingie and scroll down to select pizz for voice one.

note, it's easy to make the mistake of selecting voice 2 thinking that each sound represents a different voice but that won't work unless you have spefically written 2 different melody lines using 2 voices on the same staff. Voice 1 can be changed back and forth from arco to pizz, etc...not having voice 1 designated as arco, voice 2 as pizzo, if that makes sense... :) as I babble on.