flask_dynamicContent

from flask import Flask, render_template

app = Flask(__name__)

@app.route('/')
def home():
    return 'Welcome to the Flask App with Dynamic Content!'

@app.route('/user/<username>')
def display_user(username):
    return f'Hello, {username}!'

if __name__ == '__main__':
    app.run(debug=True)

##### index.html #####
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Dynamic Greeting</title>
</head>
<body>
    <h1>Hello, {{ username }}!</h1>
</body>
</html>