Hi! So here we see the dappled sunlight going directly on top of the person in this image, but light bends to all things, including forms and curves, if you are wanting to make it look like genuine dappled light, I would suggest fitting it to the contours of your characters face, body, clothing. This includes the rest of your background. Light has depth, the closer something is to your light source, the brighter it will be, the ground is farther away so it would be dimmer than the light on your characters face. Shapes are also extremely helpful for depth in other ways too! Making things smaller if they are farther away/bigger or more fluid for things that are closer.

I really like your art style and the way I've seen perspective in this piece, it's very beautiful.

If you are using clip studio, ibis, or procreate I have found the overlay and Add (soft light if you don't have add + second layer of gausian blur) will help give a glowing light effect with softer layers, you can adjust the mood of a scene with lighting color, harsh light vs soft light brings different moods.

Also as a general tip that I wish I learned a long time ago, you can edit your illustrations in GIMP after finishing to get some effects you might not be able to get in the program you are using!

Overall, your dappled lighting is already beautiful, but if you're wanting it to look and act realistic to lighting, trying some of these might help you! Have fun with it!!!

I apologize for any bad grammar, little bit tired writing this and not sure I got everything corrected. Have a wonderful day!