Enot990, так?
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Пример</title>
</head>
<body>
<input type="text" class="inp">
<button onclick="go();">Go!</button>
<script>
function go(){
var q = document.querySelector('.inp').value;
window.open('https://www.google.com.ua/search?q=' + q);
}
</script>
</body>
</html>