It's especially great fun to read the Henry 6 plays because you probably don't know how they end!

When this play opens, Henry the Sixth is nine months old and his dad is already dead at age 36 of dysentery (or something worse, some say). All the glory won and the political territories that were captured by Henry the Fifth are disappearing because of the bickering among the noblemen, pathetic jealousies, empty boasting, unkept promises—sheesh—while the country goes to heck in a hand-basket. Although he's a baby when the play opens, Henry gets married by the end.

To remember which Henry 6 play is which, I use the women: In Henry the Sixth, part One, watch for Joan of Arc.

Here is a detailed synopsis on Wikipedia.
And this is a chart of the actual historical characters: Historical 1 Henry the Sixth

If your group reads the plays straight through in one sitting and you want to divide up the parts, we have a number of “cast” lists already divided up for you. These are text files that you edit to suit your group. We always recommend in a straight-through read that each participant take a moment beforehand to mark their parts—then everything proceeds so smoothly. (charts coming soon)

• Cast for 8, plus a reader for Stage Directions
• Cast for 9, plus a reader for Stage Directions
• Cast for 12, plus a reader for Stage Directions

For those of you who provide parts a scene at a time, this Character Chart shows all the characters' lines in each scene: Henry the Sixth, part One

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To help you prepare for the Henry 6 plays and particularly the sequel of Richard 3, it's immensely useful and enjoyable to watch the series, The White Queen, based on books by Philippa Gregory. It is the history of the period as told by three women: Elizabeth Woodville who married King Edward 4, Margaret Beaufort whose son eventually becomes King Henry 7, and Anne Neville (Warwick the Kingmaker's daughter), who first married Edward the son of Henry 6, but after Richard's family murdered Henry 6 and his son Edward, she married Richard (eventually Richard 3). That might seem confusing at the moment, but watching the series before reading the plays makes everything much clearer.  ;–)

This is an audio recording of the play by professional actors with sound effects:

A great way to get to know the characters in the Henry 6 history plays is this series. You can find it on online streaming services as well.

You might also enjoy the original entire series of books by Philippa Gregory: