So, animating a walk in four frames (you seem to have eight- unless i got really bad at counting-, but hey, it still helps, just do the four then do the inbetweens) is relatively easy once you get the hang of it. It's literally two poses, that then repeat for the other leg to give the illusion of movement.
first pose:
-both legs on the ground
-The body is overall lower height than normal. (lower than idle)
-Left leg is all the way to the front.
(just do the legs animation apart, and just then draw the arms, it's easier to separate them mentally otherwise you might get tangled up, it happens to me if i hurry and do all at once)

-i just realized i never did a good sprite set with actual normal legs, so digitigrade we go. hope it still translates-
second pose:
-the frontward leg is now going back, but is still on the floor (it's pushing the whole body forward)
-important!!! the leg on the back lifts to let the front leg do the pushing work. It also prepares to touch the floor as to avoid making the creature fall on its face.
After all, walking is really just a controlled free fall, all time.
If you exaggerate the walk, both legs together should make a 4 if viewed form the side. I'm saying this so you have a reference!
-the body is overall taller height than normal. (taller than idle)
Now the arms. They kinda do the opposite thing. In the "middle frame" (second pose) they should be closer to the middle of the sides. In the first pose, they should be opposite to the legs. The arm that looks closer to the front is opposite to the front leg.
Now for the other two frames you do the opposite and you are golden!
most importantly have fun. Sounds lame as fuck, but hey, i have a blast doing this stuff. In slow days i at least force myself to do one frame a day, it's a good way to do work without even realizing it.