Youcan do this in FC, Motion, AE, Animate or other animation software.
Simplest way is simply to have all your pictures ready and then assemble the animation with Motion or directly in FC.
You will need to do basic animation in Motion (Fire).
Walking sequences are fairly simple.
Like with any animation, if you haven't done this before i would suggest that you try a short sequence of 10 seconds to get the hang of it.
As for the movement, well that is having a good sense of movement.
Just to add on what I said earlier.
Walking cycles that are shown are fairly simple.
A walking cycle and making characters walk is one of the most complicated animation.
A lot of personnality is based on the walking cycle.
And let's not forget you either have to be able to draw the graphics you need to start with, have access to a graphic artist or be able to get the graphics you need from a stock graphics service like Shutterstock, Vectorstock, Adobe etc. Then, you can do the animation work.
I do graphics work for TV broadcast daily, I find 99% of images I can't create myself for free, legally online. Access to stock media is a given in our business, but we canceled several subscriptions recently because we can find so much free online that is great quality and useful.
If you are up for a animation specific program you might check out Moho Pro. Smithmicro recently sold the company back to the team that originally created it. I have used to create everything from callouts to short political satire. Right now it is not compatible with Big Sur, BUT, this recent buy should handle that issue. Smith Micro hasn't been super Mac friendly for a while
It is good news that in won't be SmithMicro.
Most unfriendly service.
I had Moho but dropped it because of the crappy (my opinion) system they used to validate the software.
The whole selling method was so cumbersome and a pain.
We will have to see if the new owners clean this up.
But yes it would be an option if they upgrade service and selling method.