By default WordPress shows “admin” when you publish blog posts. That is, when you have installed WordPress on your own and you are publishing blog posts on your own, unless you make some changes, with every blog post you see “admin” instead of your name.
You can remove “admin” and show your first name or full name instead. You can either create another admin-level account with a different username and then delete the account having admin as username (all your blog posts will be allocated to the new admin), or you can simply make changes in your user information: this is the preferred way of removing “admin” from your blog posts and showing your name.
The username in WordPress cannot be changed, but you can certainly decide how the name of the author — including yours — is displayed with the blog posts. Go to your user management section from the WordPress admin:
From the available list of authors and admins decide to Edit admin. If the First Name and Last Name fields are blank, enter the right information there. You may also like to enter a nickname but this is not necessary. Then click the Update Profile button. The information will be updated but remain on the same page. Scroll down to the section that says, “Display name publicly as”. This is where you can decide what to display instead of the plain “admin”:
This is how you remove “admin” from your WordPress blog posts and use the actual name instead.