In short – no.
The receipt itinerary that is sent to your email address after payment serves as proof of purchase.
You don’t have to show it to anyone at the airport, as all your details are stored in the airline’s database, so your travel document is all you’ll need to check in.
To board the plane, you need a boarding pass, which you can get at the check‑in desk at the airport, at a self‑check-in terminal or by checking in online. In the last case you’ll receive your boarding pass by email for you to save to your phone or print out.
This is roughly what an itinerary receipt (ticket) looks like.
If your ticket didn’t arrive in your email inbox, check the Spam folder. Often emails find their way there. Learn more.