The main difficulty in using it is that almost nobody is willing to use it; as with anything, you learn do something by doing it. I only have one regular correspondent who uses encryption. But email encryption can also be difficult to use. Mailpile looked like a promising email client at one point, and for many people it probably still it, but the latest beta completely quit working for me and I had to abandon it. I now use Mailvelope, a browser extension for Chrome and Firefox which has become quite good and quite easy to use. I recommend it if you want to give PGP encryption a try.
The web-based Proton Mail is an option if you just want to use a web service similar to Hotmail, Yahoo Mail, Gmail, etc. There, the main problem is finding other folks who will use it. If you want to try it, you can write to me at firstname.lastname@example.org.