Check out example codes for "javascript prevent form submit". It will help you in understanding the concepts better.
Code Example 1
<button type="submit" onclick="submitButtonClick(event)">Submit</button>
<script>
function submitButtonClick(event) {
event.preventDefault();
//other stuff you want to do instead...
}
</script>
Code Example 2
<form name="foo" onsubmit="return false">
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