JSFiddle - React, Tailwind, and code Playground

HTML

<form action="#" id="f">
    <input type="date" id="a" name="a" required />
    <button type="submit">Submit</button>
</form>

JavaScript

$("#f").submit( function(e){
    var $date = $("#a"),
        date = new Date($date.val()),
        date2 = new Date()
    
    date2.setDate(date2.getDate() + 2)
    
    if(date < date2){
        alert("fail");
        e.preventDefault();
    }else{
        alert("Success");
    }
} );