how to manually add google adsense code in google amp

First click on Ads >> By ad unit. After this create a new ad unit.

After creating the Ad unit, you have to click on AMP >> Advance Setup >> Settings >> Advertisement. You can show advertisements on your favorite positions:

• Below the Header (SiteWide)

• Below the Footer (SiteWide)

• Above the Post Content

• Below the Post Content (Single Post)

• Below The Title (Single Post)

• Above the Related Posts (Single Post)

Wherever you want to show Adsense ad, just enable it and paste Data AD Client and Data AD Slot.