Fallout and Fallout 2 are canon according to Bethesda, and other games incorporate lore and backstory established by Fallout and Fallout 2.
Fallout 3 and its add-ons are produced by Bethesda, therefore are canon, as are all other games and supplementary materials released by Bethesda.
Fallout: New Vegas and its add-ons (with the exception of content changed with the Wild Wasteland trait), which were published by Bethesda, are canon, as are all officially released supplementary materials, like the All Roads comic.
Fallout 4 and its add-ons are produced by Bethesda and therefore canon.
Fallout 76 and its add-ons are produced by Bethesda and therefore canon.
Nuka-Cola entered the beverage market in 2044, with the invention of the soft drink by John-Caleb Bradberton after two years of experimentation. Though strictly unhealthy (containing 120% of the recommended daily allowance of sugar), it took the United States market by storm and within a year it could be purchased nationwide. Its popularity rapidly increased and within several years it was the most popular beverage across the globe.