Tales from the Yawning Portal PDF is probably a rule book for new players. It is rated by the DnD player community as fairly easy to perform tasks and adventures.
In it there are many fascinating adventures for you and your teammates. Especially with The Sunless Citadel, this is considered an adventure with 10/10 perfect points.
Tales from the Yawning Portal has beautiful and eye-catching maps. However, with this PDF you need to print in color to get the most realistic feel.