Sounds just like a screenplay, which is fine, if you're trying to make a storyboard for an animation, or a movie, but it's not a book, and it sure isn't a novel. To change a screenplay into a novel, you need a lot more.. -And I mean, A LOT MORE, words.
You have characters, and they obviously have emotions, but they don't have bodies. They say they do, but do they really?
tanenter: That’s enough! Stop pinching my cheek right now.
Yamao: Aww, but your little kid cheeks are just so squeezable.
tanenter: We’re the same age 15 year!!
Yamao: But I'm taller than you, so that makes me look more mature than you.
tanenter: God, I hate girls like you.
Yamao: Thank You.
tanenter: Bro!!! ?
Clearly, you have an image in your head of what these characters look like. (The words I highlighted in bold.)
Tell us that image.
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Normally, I would say start with the six senses.
Sight - What they see
Smell - What they smell
Listen - What they hear
Touch - What they can feel
Taste - What they can taste
Proprioception - How they carry themselves. Their movements. Their stance, balance, understanding of the space, or world around them, and how they interact. Do they have high levels of finesse like a gymnast, or an acrobat? -Or do they stumble, and bumble around like a drunken, clumsy idiot? If they don't, are they... "NoRMal"? -audible gasp
Most people would say normal is boring. Why read a boring character? Make them interesting.
Personally, I enjoy when certain characters take one of the senses, and really delve into it for no reason at all.
Kids pick up all kinds of weird behaviors. Most people simply rely on sight while moving around, and interacting with the world, but babies like to put things in their mouths, and they learn by doing so.
Some people hate lemons, or Chilis, and other love spicy, or bitter things.
There are also those that really enjoy learning the smell of others, or can smell the scent of baked goods from a mile away. Then there are people that can't even stand the smell of candles, or get allergies very easily.
There are people who hug EVERYONE, and people who don't like being touched at all.
What kind of character is your character? A character can SAY they are the most intelligent man in the entire world!!!! But can't think his way out of a paper bag with an exit sign glowing over his head, and a pair of scissors in hand.. Show -Don't tell.
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AN:
Even screenplay writers need to know the basis of show don't tell. Directors will only give a few minutes to tell the story in order to sell the script. ACTION is what sells the story, dialogue is a topping. I also started off as a screenwriter. I wanted to do animation storyboarding.
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Second:
Give your character traits, give them faults, and likes, and dislikes, give them some quirkiness, or looks, or style. Give them life, not just a mouth piece. Paint a story. If you're going to play in the mud of "he said, she said", at least make some mud angels, let them move, not just banter.
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But since you asked where to start practicing.. I'd say start practicing by reading kids books.
Kids books are loaded with stories solely moving forward in action since dialogue lead stories are more complex, needing to know who is talking, and when. dialogue driven stories are more focused toward young adults.
The Very Hungry Caterpillar
I know it might seem like I'm joking, or pulling your leg. But it's the most basic of basic children stories everyone has heard of.
The caterpillar never says a single thing, but the story moves forward through very, very simple actions.
Start with simple actions.
Move to more advanced actions.
Write an entire page without dialogue.
Use your characters body language, and motions to do things.
If they must talk, talk for them, don't allow them to use quotations.
Then add dialogue as the topping.
Mix it up to make it appetizing.
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Ex:
Kids story
Girl looked outside at the lake. She wanted to go swimming. Boy did not. He had told her it was far too cold, but she did not listen. She went outside, and leapt into the small lake despite his warning; Only to, moments later, come back inside, absolutely, shivering. Boy saw her, and ran toward the closet, bringing her a warm, heavy blanket. He shook his head as if to say, he had told her so, but instead chose to say nothing. Her shivering was punishment enough.
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Screenplay
G: "I want to go swimming!"
B: "No. It's too cold.."
G: "If you're not coming with me, I'll go by myself!"
B: "I'm telling you not to.."
G: "I'M LEAVING!"
Girl goes swimming.
Girl returns.
G: "..I-it's fr-freezing.."
B: "Damn it all.. I'll get you a blanket!"
Girl shivers.
B: "..."
=
Novel
Girl looked outside at the lake. "I want to go swimming!" she said excitedly.
Boy did not. "No. It's too cold.." He muttered, but she wouldn't listen.
"If you're not coming with me, I'll go by myself!" She cried.
"I'm telling you not to.." He warned.
But despite him, she went outside. "I'M LEAVING!" She yelled, and ran toward the lake, leaping in.
Moments later, the door reopened. "..I-it's fr-freezing.." She whimpered, absolutely shivering.
Boy saw her. "Damn it all.. I'll get you a blanket!" He ran toward the closet, bringing her a warm, heavy blanket.
She shivered as he shook his head as if to say, he had told her so.
"..." But, her shivering was punishment enough, he thought.
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It's a matter of how you want to present yourself, and your writing.
My example is very bland, and obviously not A+ material, it was just an example. Your story is going to want to be more than that, with names and emotion, and structure.
