This blog post will be making a tutorial on how to hide the share button on the blogger which is the default version provided by blogger. It up to you to remove it or not but if you want a professional-looking blog by using a custom theme and custom share buttons. I would suggest you remove it and use share buttons that are available in the free or paid version.
Which can be incorporated by copying and adding their HTML code to your blog. They all have a directional blog page which you can follow to add them to your blog
FIRST, Go to your blogger blog interface you will find the settings of a blogger on your the left side of a blogger and choose or click on LAYOUT
SECOND, The main page or blog post you will find an EDIT button on the lower or upper part of the blog post or main page and click on it
THIRD, You will have a popup page where more editing options with a box to tick or not. Look for SHOW SHARE BUTTON on the list once you find it remove the tick from the box
LASTLY, Do not forget this, Scroll down and click on the SAVE button for changes to happen on your blogger