In blogger, by default, post published date will be above post title and on the left-hand side. But this is just by default. If you want this date to be in center or on right-hand side, you can have by adding a stanza of customized secondary CSS.
Let me guide you step by step in re-positioning a post published date either in center or right-hand side of the post body.
Login to your blogger account
Select the blog (if you have more)
Select the drop-down menu of the blog
Select template button
Click on customise button
Click on Advanced
Click on Add CSS
In add custom CSS, copy and paste the given CSS code:
Click on Apply to blog. View blog. Post published date be re-positioned. And if you want that date to be in center, you can just change red font in step# 9 into center.