No, humans do not become angels after death. The Bible teaches that humans and angels are distinct creations with different roles and natures. After death, humans experience a separation of body and soul, with the soul going to be with Jesus or to a place of torment, based on whether or not that person trusted in Jesus’s death and resurrection for the forgiveness of sins. In the end times, believers will receive glorified bodies and live in paradise, while unbelievers will face judgment, but humans never transform into angels.
At no point does the Bible indicate that humans become angels after death. At death, the body and soul of a human are separated. The soul of the believer goes to be with Jesus (2 Corinthians 5:6–8), and the soul of the unbeliever goes to a place of torment (Luke 16:22–23). At the end times, believers (1 Thessalonians 4:13–17) will receive new, glorified bodies and spend eternity in paradise (Revelation 21:1). Unbelievers (Revelation 20:11–15) will be judged and cast into the lake of fire. No work as an angel is mentioned. God created humans and angels to glorify Him but in different ways. Occasionally, our paths cross as we work together for the kingdom of God. In heaven, we will glorify God with the angels, but we will never become them.