How to pass a variable data into the HTML file?

use rand::Rng;

#[derive(Debug, Deserialize, Serialize)]
struct RangeParameters {
    start: usize,
    end: usize
}

async fn handler_random_number_generator(Query(params): Query<RangeParameters>) -> impl IntoResponse{
    let random_number = rand::thread_rng().gen_range(params.start..params.end);
    Html(include_str!("../index.html"))
}

I want to pass the random_number in the index.html file as a value for some a placeholder. Is this possible?

I have achieved this by using the askama crate:

use rand::Rng;

#[derive(Debug, Deserialize, Serialize)]
struct RangeParameters {
    start: usize,
    end: usize
}

#[derive(Template)] // this will generate the code...
#[template(path = "hello.html")]
struct RandomNumber {
    random: usize
}

async fn handler_random_number_generator(Query(params): Query<RangeParameters>) -> impl IntoResponse{
    let random_number = rand::thread_rng().gen_range(params.start..params.end);
    let random = RandomNumber {
        random: random_number
    };
    Html(format!("{}", random.render().unwrap()))
}