You can download OneNote in the correct version for your system or device through available links at OneNote.com.

You can use Notes on iCloud through your iPhone, iPad, or Mac, or in a browser using iCloud's website, to create, edit, and view synced notes.

There’s been plenty of research that has suggested hand-taken notes are superior to those you take on a computer, even though typing is so much faster and you can get more information on the page.