As far as the public knows, no, Kylie and Travis are not engaged. However, back in November 2021, many fans thought Travis has popped the question after Kylie was seen rocking a huge diamond ring on her finger right before the AstroWorld tragedy. The rapper had gifted her the gorgeous rock and was sure to buy a matching miniature version for their daughter, Stormi. Kylie, however, only wore the ring on her index finger.
The rumors eventually died down.
Source: https://www.distractify.com/p/are-travis-scott-and-kylie-jenner-married