We can create a simple form action to google.com/search by using the attribute of the form.
The name of the first input called q, it is because this input can be used like ?q=input, at the end of the google.com/search, which can do a GET from google website with the input named q.
<form action="https://www.google.com/search" method="get">
<input name="q" type="search">
<input type="submit" value="search">
</form>
