Solution
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
$(window).scroll(function () {
$("input").blur();
});
</script>
Example
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<style>
header {
position: fixed;
top: 0px;
left: 0px;
background: #673ab7;
width: 100%;
min-height: 200px;
padding: 30px 0px;
color: #fff;
text-align: center;
font-size: 20px;
text-transform: capitalize;
z-index: 99;
display: flex;
align-items: center;
}
.demo {
font-size: 42px;
background: red;
color: #fff;
padding: 20px;
margin-bottom: 100px;
}
</style>
<header> this is header</header>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<input type="text">
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<div class="demo"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Earum corporis, consectetur tenetur
dolor veniam nesciunt odio excepturi aut culpa? Molestias laboriosam magni libero dolorem nobis, asperiores vero
possimus! Accusamus, excepturi?</div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
$(window).scroll(function () {
$("input").blur();
});
</script>
</body>
</html>