Short answers, pulled from the story.
Scott Lang was released from prison in 2015 after serving time for a burglary. He found his life in shambles upon release, with his wife having divorced him and taken custody of their daughter Cassie.
Hank Pym orchestrated the test that led Scott Lang to steal the suit. Pym manipulated Scott into stealing the motorcycle-looking suit to prove he could be trusted with the technology.
Scott Lang spent what felt like five hours inside the Quantum Realm, but five years had passed in the outside world. He was accidentally left behind when the Quantum Realm's portals closed during the mission to rescue Janet van Dyne.
Scott Lang wrote a memoir titled Look Out for the Little Guy. The book reflects on his journey from a thief to a hero and emphasizes the importance of family and redemption.
The suit's technology is based on Pym Particles, which allow Scott Lang to manipulate his size and strength. These particles enable him to shrink to subatomic size or grow to enormous sizes.