How can I correctly add the lib with jqueryUI

How can I correctly add the lib with jqueryUI

Good day,

I spend a lot time to make my jquery mobile web site, and I particularely spent time to understand with the jquery UI, change my layout.

I need to add a datepicker, this is the reason why I added (only because the datapicker layout)
  1. <script src="js/jquery-ui-1.12.1/jquery-ui.js"></script>
  2. <!--    <link rel="stylesheet" href="css/jqueri-ui-1.12.1/jquery-ui.css">-->
But since I uncomment the jquetyui CSS file, the content of my web site change.
Then I wonder how can I use it.

Is there a way to work without it?

Now I wonder, if I corretely add the library. I am worried because here
Latest stable version it said to add jquery.1.11
and I am very confused with this because I can read here Jquery last version , the last version is 3.3.1.

So what's the difference between 
   

    

     jquery-1.11.1.min.js and jquery-3.3.1 ??
    

    

     

    

    

     Do I prepare my file correctly as well? Could you confirm me?
    

    

     

    

    
    
     
  1. <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <title>Foxuino - Perrieres</title>

     <link rel="stylesheet" href="js/jquery.mobile-1.4.5/jquery.mobile-1.4.5.min.css" />
     <!--<script src="http://code.jquery.com/jquery-1.11.1.min.js"></script>-->
     <script src="js/jquery.mobile-1.4.5/jquery.mobile-1.4.5.min.js"></script>
     
       <!-- Chartjs -->
     <script src="js/moment.js"></script>
     <script src="js/Chart.js-2.7.2/dist/Chart.js"></script>
     <script src="js/Chart.js-2.7.2/samples/utils.js"></script>

     <script src="js/jquery-ui-1.12.1/jquery-ui.js"></script>

    <!-- <link rel="stylesheet" href="css/jqueri-ui-1.12.1/jquery-ui.css">-->
     <link rel="stylesheet" href="css/style.css">

    </head>
    2. 
    

    

     
     

    

    

     So to resume my questions:
    

    

     Do I impement correctly jquerymobile?
    

    

     What's the difference btw 
     query-1.11.1.min.js and jquery-3.3.1 ??
    

    

     How can I use jqueryMobile and Jquery UI css file together?
    

    

     

     
    

    

     Many many thank for your help and support.