Ctrl+K / ⌘K will bring up the quick commands palette.
Type what you want to do and then select the command from the list to run the command.
Your most frequently used commands will display with the actual shortcuts, so you can learn them over time.
List of commands and shortcuts:
⌘ X Cut
⌘ C Copy
⌘ V Paste
⌘ Z Undo
⌘ A Select all
⬆ ⌘ Z Redo
⌘ B Bold text
⌘ i Italicize text
⌘ U Underline text
⬆ ⌘ X Strike-thru text
⬆ ⌘ U Make UPPERCASE
⌥ ⌘ U Make dual dialogue
⬆ ⌘ E Center paragraph
⬆ ⌘ B Add connected beat
⬆ ⌘ C Manage collaborators
⌥ ⌘ S Create alternate draft
⬆ ⌘ S Take snapshot
⬆ ⌘ H Open version (older draft)
⌥ ⌘ A Save paragraph as alternate
⬆ ⌘ A Open paragraph alternates
⌥ ⌘ B Open Plot Board
⌘ F Search
⌥ ⌘ 1 Show Drafts sidebar
⌥ ⌘ 2 Show Contents sidebar
⌥ ⌘ 3 Show Comments sidebar
⌥ ⌘ 4 Show Notes sidebar
⌥ ⌘ 5 Show Stash sidebar
⌥ ⌘ 6 Show Story Elements sidebar
⌘ D Toggle Focus Mode
⌘ M New global comment
⌥ ⌘ M Start a comment for highlighted section
⌘ , Open All Settings
⬆ ⌘ I Document information
⌘ O Open script
⌥ ⌘ Tstart 25 min sprint timer
⌘ E Export
⌘ = Zoom in
⌘ - Zoom out
⌘ W Return to desk
⌥ ⌘ K Jump to previous revised section
⌥ ⌘ J Jump to next revised section
⌥ ⬆ ? Search knowledge base
⌥ ⌘ → Toggle to the next view (Script to Plot Board, Plot Board to Outline, and Outline to Script)
⬆ ⌘ F document formatting
⌘ ? connect to support