Hello!
I am a newbie too, and experiencing troubles of my own!
For walk speed, I did and redo a good tutorial about characters, but only third person… To me, the walk speed can be defined first in the Blend Space of your character, when you dragged your walking animation in, and in the nodes inside the blue print of your character. I followed the tutorial in French to set my blue print, I don’t know if there are other ways to work, but
I have 2 nodes in it named “Set” in which I can define the walk speed, so the computer know s when the character is supposed to walk and when it is supposed to run.
I hope this helps…
Good luck, I know it is difficult, but it’s fascinating to learn Unreal! 