This code sets the header and footer.
CSS:
footer {
width: 100%;
position: fixed;
bottom: 0;
right: 0;
background: black;
color: white;
height: 40px;
display: flex;
}
header {
width: 100%;
position: fixed;
top: 0;
left: 0;
color: white;
background: black;
height: 40px;
}
HTML:
<html>
<body>
<header>
Este é o cabeçalho
</header>
este é o corpo
<footer>
Este é o rodapé
</footer>
</body>
</html>
The CSS rules that are important to the desired effect are:
position: fixed
top: 0
bottom: 0
right: 0
left: 0
They instruct the code to fix the elements and in what positions.
From this, it is easy to adapt to your case.