Insert the Adsense code manually to WordPress Site

Follow the following step to add your Adsense code to manually your website:

To do one: Log into your WordPress admin dashboard. Go to Appearance > Editor:

To do two: Select your current theme from the drop-down menu Select theme to edit in the top right corner. Then, choose Theme Header (header.php) template from the list on the right:

To do three: Find the tag and paste the verification code from Google AdSense right after it. Save the changes:

To do four:  Return to your Google AdSense account, check the box to confirm that you pasted the code and click Done:

To do five:  Return to your Google AdSense account, check the box to confirm that you pasted the code and click Done:

You can also add your Adsense code using a plugin:

Use Plugin to add you code