According to Scripture, that is not true.
Paul knew he was going to die. He just wasn’t sure when or how. But he knew it was coming. And he knew that other Christians would remain after he died.
Reference: Acts 20:17-37.
I would be interested in any reference you may have that Paul believed Christ would return in his lifetime.
It is true that believers have expected Christ to come. However, the current belief among Fundamentalists, propelled by Scofieldism and based on the hallucinations of a teenaged girl in the 1830’s has risen to almost cult proportion.
BTW, I am an Evangelical, raised in the Fundamentalist tradition.
Fundamentalists... based on hallucinations of a teenage girl in the 1800s? True fundamentalists base nothing on anything from the 1800s. Everything is based on the Scriptures only. People who base any faith or doctrine on something extra-Biblical, e.g., from the 1800s, would be involved in a cult.