Short answers, pulled from the story.
The first issue of the Fantastic Four was cover-dated November 1961. This issue introduced a bickering family of celebrities who wore their powers on their sleeves and their names in the headlines.
Stan Lee and Jack Kirby created the Fantastic Four, though the credit remains a contentious debate between the two creators. The story began with four civilian astronauts, Reed Richards, Ben Grimm, Susan Storm, and Johnny Storm, who were exposed to cosmic rays during an unauthorized test flight into outer space.
The Galactus Trilogy began in issue 48, cover-dated March 1966, and is frequently cited as the finest achievement of Lee and Kirby's run on the title. This three-part saga introduced the cosmic giant Galactus and his herald, the Silver Surfer, to the Marvel Universe.
The wedding of Reed Richards and Sue Storm took place in Fantastic Four Annual 3 in 1965. This event marked the first time that a superhero team had a wedding in a mainstream comic.
The birth of Franklin Richards, the son of Reed and Sue Storm, occurred in Fantastic Four Annual 6 in 1968. This event was one of the first times that a superhero team had a child in a mainstream comic.
John Byrne's run on the Fantastic Four began with issue 209 in August 1979. This run is widely regarded as one of the greatest in the history of the series and revitalized the title with a focus on the team's family dynamic.