Everyone gets Movement, Action, Bonus Action, Reaction (In Game).
Reactions (default) are basically taking attacks of opportunity, can also be spells like Hellish Rebuke. Toggles on the far right hotbar.
Dash doubles your move, everyone can do this as an Action (instead of casting / attacking). The Rog 2 ability OP asked about, lets you Dash as a Bonus action, allowing you to Cast / Attack as well.
