There are two ways of adding meta tag in your blogger blog.
First way is log in to your blogger blog than go to Blogger Settings > Search Preferences .There is option to add meta tab in which have to allow permission to use meta tab make that option as “YES”. Than write you meta tag which is suitable for your blog.
Second way is manual installation, in which you have to create your own meta tag with html code and you just need to install it just below <head> tag in your blogger blog. Don’t be tense if you don’t know how to create meta tag html code simply follow steps which are mentioned below.
Step 1: generate your meta tag and copy that code.
Step 2: Log in into your blogger blog. And backup your template. ( How to backup your blogger template? )
Step 3: Now select Template > Edit HTML > Proceed button.
Step 4: Than find <head> tag by pressing (Ctrl+F).
Step 5: Now past your meta tag ( which we created in step 1 ) Just below <head> tag.
Step 6: Save it. That set. Your meta tag is successfully installed.