If you're using Google Chrome then download this extension "DuoKeyboard" for the desktop version of Duolingo.

https://chrome.google.com/webstore/detail/duokeyboard/dekooljcgfaiokofbciaflklkfniimfa?hl=en

If you want to type in Hebrew on your phone in the Duolingo App then just go into your phone's language settings and add a Hebrew keyboard.

I was using the Microsoft onscreen keybd - it worked fine except quite often when I summoned it up to use - it would lock up for 20 seconds before I could use it - I will try the Duolingo keybd Thanks

I'll add another suggestion - copy-paste from "gate 2 home" website (online keyboard, doesn't not require installation).