What activity can a character integrate into a prepared action? According to the rules, I know that I can do an action or move. What about other types of actions: reaction, bonus action, free action, speech (and any other actions that I've forgotten / that I do not know). Examples:
Can I speak while exercising my prepared action? As if my prepared action is to stab someone and shout "cowabunga!" when they walk by. According to this question, it seems that you can not speak normally outside your turn.
Can I use a free action when performing my prepared action? Like moving and opening a door on my way.
I think I can not use a bonus action based on my prepared action, and reactions react normally.
I do not know if there are certain types of actions missing, but I hope that this question is sufficiently precise.