demo.html

login.html 

<ul class="nav flex-row" id="menu">
    <li>
        <a href="/" class="nav-link">Link</a>
    </li>
    <li>
        <a href="/" class="nav-link">Link</a>
    </li>
    <li>
        <a href="#theModal" class="nav-link" data-remote="/render/xJCCbGB5oA" data-toggle="modal" data-target="#theModal">Register</a>
    </li>
</ul>

does code below part of login.html?

<div class="modal fade" id="theModal" tabindex="-1" role="dialog">
    <div class="modal-dialog" role="document">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title" id="exampleModalLabel">My modal</h5>
                <button type="button" class="close" data-dismiss="modal" aria-label="Close">
                    <span aria-hidden="true">×</span>
                </button>
            </div>
            <div class="modal-body">
                ... remote content from "data-remote" loads here ...
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
                <button type="button" class="btn btn-primary">Send message</button>
            </div>
        </div>
    </div>
</div>


I want to load a pop-up form that goes to another page register.html after clicking 

<script type="text/javascript">
	var button = $(e.relatedTarget);
    var modal = $(this);

    // load content from HTML string
    //modal.find('.modal-body').html("Nice modal body baby...");

    // or, load content from value of data-remote url
    modal.find('.modal-body').load(button.data("remote"));


</script>



 register.html 

    <form class="form-horizontal">
                    <div class="form-group">
                        <label for="inputEmail3" class="col-sm-2 control-label">Email</label>
                        <div class="col-sm-10">
                            <input type="email" class="form-control" id="inputEmail3" placeholder="Email">
                        </div>
                    </div>
                    <div class="form-group">
                        <label for="inputPassword3" class="col-sm-2 control-label">Password</label>
                        <div class="col-sm-10">
                            <input type="password" class="form-control" id="inputPassword3" placeholder="Password">
                    </div>
                    <div class="col-sm-10 col-sm-offset-2">&nbsp;</div>
                    <div class="form-group">
                    <div class="col-sm-10 col-sm-offset-2">
                  <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
                  <button type="button" class="btn btn-success" data-dismiss="modal">Submit</button>
                    </form>