How do you create the separate parts in musescore 4?

Hi,
I have just moved over to musescore 4 - and I cannot see how to create the individual parts from the main score as you used to in musescore 3.

Please tell me this hasn't gone.

I know I can export the separate parts as pdfs - but you can't adjust stretch / page turns etc - and it's much harder to input on the full score when working on a small screen such as a laptop.

I can't find anything in help so far - hopefully someone knows....