<div class="container ">
        <div class="row d-flex text-center align-self-center">
            <div class="col-12 ">
                <h1>The Biggest Startup Event Of The Year</h1>
            </div>
            <div class="col-12 ">
                <button type="button" class="btn btn-danger">Find Out More</button>
            </div>
        </div>
</div>

the div should be in middle of the page