Unlike Samsung and Microsoft’s pen solutions, Apple’s Scribble handwriting recognition has to be programmatically added to each application it is used in. This has contributed to a slow rollout of the popular feature.
Microsoft Word mobile was the app I wanted it to work most in. I had given up checking whether or not it had been added a while back. Just out of necessity, I accessed the draw tab in Word on my iPad today and noticed a new icon in the pen carousel, it activates Scribble.

I checked Excel and it works the same way there. It is also available in PowerPoint, but it is missing from the OneNote app. Open the Draw tab from the file menu and select the Apple Pencil icon to enable Scribble, then you can use your Apple Pencil to write on the screen in any space that would normally take typed text as input.
For a better experience, keep your handwriting as straight as you can. Writing a little larger than you are used to also helps. Print will probably be the most accurate, but Scribble can understand cursive and the combo I seem to write in most often.
If it doesn’t work with your Apple Pencil, make sure that you have the latests software updates installed. Check in settings to be sure the feature is enabled. There’s also a tutorial wizard that teaches you how to use Scribble in the settings app.
