if I click on linked text can I add a smooth swipe to the top ?

Hello! As it is said before, you have to use JavaScript or it's library Jquery for that. You can do it like this:

Asign the same class (in my example I called it "link", but you can choose any adding the same changes to the script) to all links you want to use in swipe. Also give unique id to each page block you want to scroll smoothly and a href to the link like this.

           <p id="about"> Information about company and so on. </p> 
            <li><a class="link" href="#about ">About</a></li> 

Then add the code below before your closing </body> tag. 1500 (stands for speed, you can do it faster or slower as you prefer, giving more or less number accordingly).

<script
          src="http://code.jquery.com/jquery-3.2.1.min.js"
          integrity="sha256-hwg4gsxgFZhOsEEamdOYGBf13FyQuiTwlAQgxVSNgt4="
          crossorigin="anonymous"></script>

        <script type="text/javascript">
          $(document).ready(function() {
            $("a.link").click(function () {
              var clicks = $(this).attr("href");
              var scrolls = $(clicks).offset().top;
              $('html,body').animate(
               { scrollTop: scrolls }
               , 1400 );
              return false;
            });
          });
        </script>

It cannot be done without adding some JavaScript.

As a simple analogy, think of a website like this:

The HTML serves as the skeleton/outline of the website.

The CSS changes the look of the site.

The JavaScript changes the behavior of the site.

What you're describing (adding a smooth swipe to the top) would fall under the behavior category. So I would say go ahead and try to add it to your site by learning some JavaScript.

EDIT: fixed a sentence.