First Step:-


Go To Blogger.com >> Your Blog >> Theme>>3 dots>>Backup Theme.
Now Backup your template.

Second Step:-


Then select Edit HTML >> Proceed

Search for <head> and just below it paste the following  CSS code.

<link href='//maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css' rel='stylesheet'/>

Third Step:-


Search for </head> and just below it paste the following  CSS code.

<style>
.tybar{width: 100%;
margin: 0;
height: 50px;
display: table;
font-size: 17px;
line-height: 50px;
font-weight: 600;
-webkit-font-smoothing: antialiased;
color: rgb(255, 255, 255);
    font-family: Ruda;
border-color: rgb(255, 255, 255);
background-color: #0e1032;
box-shadow: 0 1px 3px 2px rgba(0,0,0,0.15); 
text-align: center;}
.tybar .bar-but{font-size: 17px;
font-weight: bold;
margin-left: 25px;
background: #fff;
padding: 5px;
color: #fff;
background-color: #f2132d;
line-height: 1.05;
padding: 4px 15px;
cursor: pointer;
text-decoration: none;
border-radius: 3px;}
.tybar .bar-but a{color:#fff;    text-decoration: none;}
.tybar i {
float: right;
padding-right: 40px;
cursor: pointer;
line-height: 50px;
}
body{margin-top:-49.33px;}
body{margin-top:49.33px ;transition:600ms;-webkit-transition:600ms;-moz-transition:600ms;-o-transition:600ms;}
.toggleclose{top:-75px!important;}
.togglebody{margin-top:0!important;}
.fa-arrow-down {
position: fixed;
right: 30px;
top: -2px;
background:#00BE98;
color: #FFFFFF;
width: 40px;
height: 30px;
border-radius: 3px;
line-height: 26px!important;
padding-top: 10px;
padding-right: 0!important;
}
.tybar{z-index:99999;top:0;transition:600ms;-webkit-transition:600ms;-moz-transition:600ms;-o-transition:600ms;position:fixed}
.blink_me {
color:#f2132d;
margin-right:10px;
    -webkit-animation-name: blinker;
    -webkit-animation-duration: 1s;
    -webkit-animation-timing-function: linear;
    -webkit-animation-iteration-count: infinite;
 
    -moz-animation-name: blinker;
    -moz-animation-duration: 1s;
    -moz-animation-timing-function: linear;
    -moz-animation-iteration-count: infinite;
 
    animation-name: blinker;
    animation-duration: 1s;
    animation-timing-function: linear;
    animation-iteration-count: infinite;
}
@-moz-keyframes blinker {
    0% { opacity: 1.0; }
    50% { opacity: 0.0; }
    100% { opacity: 1.0; }
}
@-webkit-keyframes blinker {
    0% { opacity: 1.0; }
    50% { opacity: 0.0; }
    100% { opacity: 1.0; }
}
@keyframes blinker {
    0% { opacity: 1.0; }
    50% { opacity: 0.0; }
    100% { opacity: 1.0; }
}
@media screen and (max-width:800px) {
.tybar{display:none;}
body {
    margin-top: 0;
    }
}
</style>
<script>
//<![CDATA[
jQuery(document).ready(function(){
  jQuery( '.tybar i' ).click(function() {
  jQuery( '.tybar' ).toggleClass( 'toggleclose' );
  jQuery( 'body' ).toggleClass( 'togglebody' );
  jQuery( '.tybar i' ).toggleClass( 'fa-times' );
  jQuery( '.tybar i' ).toggleClass( 'fa-arrow-down' );
});
});
//]]>
</script>

Fourth Step:-

Search for <body>  and just below/after it paste the following coding. if you don't find <body> then search for <body expr:class='data:blog.pageType'>

<div class='tybar'>
 <span class='blink_me'>Red Text</span>Normal White Text<span class='bar-but'><a href='#'>Button Text</a></span><i class='fa fa-times'/>
 </div>