How to put the edited contents on to do list

I’m trying to create a to-do list app by vanilla JS.
I created some main functions but now I’m stucking in 2 points.

1st.
I created an “edit” button. this button adds input textbox element into li element that surrounds each to-do task by using a map method.However, I can’t come up with a proper way to replace an original wrtten tasks with a text contents in input textboxes when I finish editing.
So, I would like you to tell me how to write a “compEdit” function in the source code below.

2nd
When I add several tasks and push an edit button of other than 1st task, too many input text boxes are created.Probably, the number of created textboxes is as same amount as the element in arrayItems.

I suppose using map method itself is a wrong aproach.But I can’t come up with a good alternative.
I’ll be glad if someone tell me a proper way and why the bug in 2nd question happens.

Source code is here

//grab the elements
const todoText = document.getElementsByClassName('todo-text')[0];
const todoBtn = document.getElementsByClassName('todo-btn')[0];
const inputTask = document.getElementsByClassName('input-task')[0];
const arrayItems = [];

//function to add tasks
const addTask = (task) => {
    const listItem = document.createElement('li');
    const showItem = inputTask.appendChild(listItem);
    showItem.innerHTML = task;
    listItem.classList.add('list-item');
    arrayItems.push(listItem);

    //create a delete button
    const deleteBtn = document.createElement('button');
    deleteBtn.innerHTML = 'delete';
    listItem.appendChild(deleteBtn);

    //call a function when the button will be clicked
    deleteBtn.addEventListener('click', () => {
        deleteTask(deleteBtn);
    });

    //create an edit button
    const editBtn = document.createElement('button');
    editBtn.innerHTML = 'edit';
    listItem.appendChild(editBtn);

    //call a function when the button will be clicked
    editBtn.addEventListener('click', () => {
        editTask(arrayItems, listItem);
    });

    
};

const deleteTask = (deleteBtn) => {
    const chosenItem = deleteBtn.closest('li');
    inputTask.removeChild(chosenItem);
};

const editTask = (els = [], inputTask) => {

    //create a textbox into list items
    inputTask.innerHTML = els.map((el, i) =>    {
    return `
    <input type="text" class="editing-text[${i}]" name="item[${i}]" required>
    <input type="submit" class="complete-btn" value="complete">
    `
});

    //grab the elements of "edit button" and text into it
    const editingText = document.getElementsByClassName('editing-text')[0];
    const compBtn = document.getElementsByClassName('complete-btn')[0];

    //the function to complete editing
    const compEdit = () => {

} 

compBtn.addEventListener('click', compEdit);
}



todoBtn.addEventListener('click', () => {
    const task = todoText.value;
    if(task == ''){
        return;
    }
    addTask(task);
    todoText.value = '';
});
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="/style.css">
</head>
<body>
    <div class="wrap">
        <header class="header">
            <h1>Welcome!</h1>
        </header>
        <section class="add-todo">
            <div class="list-title">
                <h2>Add your task</h2>
            </div>
            <div class="contents-wrapper">
                <div class="list-contents">
                        <input type="text" name="todo" class="todo-text">
                        <input type="submit" value="add" class="todo-btn">
                </div>
            </div>
        </section>
        <section class="current-tasks">
            <div class="current-tasks__title">
                <h3>current tasks</h3>
            </div>
            <div class="tasks-wrapper">
                <ul class="input-task"></ul>
            </div>
            
        </section>
        <footer></footer>
    </div>
    <script src="/main.js"></script>
</body>
</html>