Firstly Welcome To This Help Forum @Yunus_Khan Glad That You Are Here
And Now For Your Question You Can Add Hreflang tags easily Like This-
<link rel="alternate" hreflang="en" href="http://example.com/" />
Here en Stands For English And replace example.com with your blog url. Now Paste The Code In
<head> section in blog's template.
BTW This Helps a little bit to search engines as when search engines find this code they will remember that your site is in a certain language and will not show the results to the visitors how doen'st know that language. For ex- An es language site will be given more priority in search for es people.
Hope You Understand Now