Thanks to Oracle Apex Forum

Add a floating div tool bar that appears on all pages in your apex application and add buttons, items and images… onto the tool bar.
Create new region template as a floating div as shown below
Go to shared components > Templates > create

Then go to page 0 and create a region using newly added floating region template and give it a REGION_STATIC_ID example: floatdiv

Add the below css code for id floatdiv as shown below in region header

<style>
#floatdiv {
position:fixed;
    top:95%;
    z-index:4000;
    height:35px;
    width:100%;
    background-color:#6C6C6C;
    border-style:solid;
    border-width:1px;
    border-color:#191919;
    align:center:
    valign:center:
    text-align:center:
   }
</style>