How to make nested form groups in bootstrap?

Question

Hi team

I want to align dropdownlist next to my modal pop up, currently dropdownlist is below this and does not look good.

// Logic

// Bootstrap code
<div class="container">

    <!-- Trigger the modal with a button -->
    <button type="button" class="btn btn-info btn-lg" data-toggle="modal" data-target="#myModal">POC</button>
    <!-- Modal -->
    <div id="myModal" class="modal fade" role="dialog">
        <div class="modal-dialog modal-lg">

            <!-- Modal content-->
            <div class="modal-content">
                <div class="modal-header">
                    <button type="button" class="close" data-dismiss="modal">&times;</button>
                    <h4 class="modal-title">POC Document</h4>
                </div>
                <div class="modal-body">

                    <embed src="~/Content/Time-Line Application_POC.pdf"
                           frameborder="0" width="100%" height="400px">

                    <div class="modal-footer">
                        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
                    </div>
                </div>

            </div>
        </div>
    </div>
</div>


<div class="form-inline">
    <button type="button" class="btn btn-lg btn-primary" data-toggle="modal" data-target="#myModal">POC</button>

    <!-- Modal HTML -->
    <div id="myModal" class="modal fade" tabindex="-1">
        <div class="modal-dialog">
            <div class="modal-content">
                <div class="modal-header">
                    <h5 class="modal-title">Checklist System</h5>
                    <button type="button" class="close" data-dismiss="modal">×</button>
                </div>
                <div class="modal-body">
                    <!-- Basic dropdown -->
                    <a class="btn btn-primary dropdown-toggle mr-4" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Basic dropdown</a>

                    <div class="dropdown-menu">
                        <a class="dropdown-item" href="#">Action</a>
                        <a class="dropdown-item" href="#">Another action</a>
                        <a class="dropdown-item" href="#">Something else here</a>
                        <div class="dropdown-divider"></div>
                        <a class="dropdown-item" href="#">Separated link</a>
                    </div>
                </div>
                </div>
            </div>
        </div>
    </div>

                <!--Building up some dropdown list for checklist Application-->