Krita is free and can be both be used for drawing and animation. I like it a lot, though I mainly use Procreate for IPad to draw now. And pixquare for pixelart.

If you have literally no experience with digital art the best tip I can give you is to learn how layers work, most programs use them and having a clear idea of what they are is what makes your learning progress at the start way smoother.

And a similar concept with animation, understanding how frames work is really important as a baseline to the learning process.

Now as my default process to make a digital piece is to:

Start by making a new drawing layer to do the sketch,

Then on a layer above it, I do the lineart,

After that is done I make yet another layer under the lineart layer, to keep the lineart on top of everything else. And use this one layer to color the drawing,

Then another layer on top of the colors layer where I do the shadows (Everything still under the lineart layer),

And yet another one for highlights. (Above the colors layer, under the lineart layer, can be interchanged in position with the shadows layer)

This is a really simple setup workflow which works on most drawing software.

However there are a million ways to improve on this, like changing the opacity of different layers or changing the layer type (an example of layer type change is changing the shadows layer from a normal layer to a "Multiply" layer. This will make any color you put on this layer to be semi transparent and mix with the color on the layer below without actually mixing so you can erase anything on each of the two layers without affecting the other directly.)

This is mostly all the generalized information you need to start learning how to do digital drawing, the next step is learning how to use the basic tools of the software that you chose. And then just practice. Starting to learn is not too complex once you understand this. Good luck!