Unfortunately, Electrum does not allow you to generate nested SegWit addresses which are backwards compatible.
That isn't entirely accurate. Electrum DOES allow you to create the "3"-type P2SH "nested" SegWit wallets... it just doesn't do it with "Electrum" seeds... only with BIP39 seeds and is probably not really a "beginner level" exercise. 
I have actually mentioned it in the next sentence without giving further explanation. I will include that in my next tutorial.
Quote
However, it is possible to import a nested SegWit address private key if you created your wallet on a website which supports this type of address
@pooya87 Thanks for your suggestions. I will edit my tutorial once I have some spare time. I will try to finish a tutorial on more advanced features of Electrum by the end of this week. Do you have any idea which more advanced features of Electrum might be difficult to use for some people?