The purpose of an e-ticket is to prove the purchase of an air trip, whereas the boarding pass is the record that shows you have checked-in and are allowed boarding the airplane.
Go to your airline's official website to see its check-in possibilities, as well as additional information that may help you alleviate flight-related worries. We advise you to study the above-mentioned-data during the booking process and days before the flight itself. This way you will make sure all the procedures have been done correctly and in time.
(Note: In case if the airline does not provide online check-in options, take the e-ticket to the airport and, the airline encounter will issue a boarding pass.)
In addition to this, we highly recommend you revise and confirm the itinerary with the carrier 72 hours before the take-off it'll help you stay up-to-date on last-minute changes.