Does anyone know the steps/items needed? I want my trailer to include my main character walking and talking in it.
This can be quite an undertaking;
Figure out your end goal:
Storyboard the sequence**
-this will drive how many and what animations you need.
-make those animations
-script, get a writer or write it out, how long is it? how many lines are there? VO or silent?
Where is it?
Create an asset list of what you need - can you use free marketplace assets? (I would start there for a simple scene blockout)
Matinee or Sequencer?
Block out the storyboard, camera angles and shots.
There is more to consider - but start with those.