<!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>PiedPiperCoin</title>
<link rel='stylesheet' href="main.css">
</head>
<body>
<div class="header">
<img src="Vector2.png" alt="Vector">
<img src="Vector.png" alt="Vector2">
</div>
</body>
</html>
div.header{
position: fixed;
background-color: #007765;
width: 1219px;
height: 84px;
}
img{
position: inline-flex;
justify-content: flex-start;
align-items: center;
}
блок div должен быть fixed.