Install an AMP plugin, it is recommended to use the AMP plugin by Automattic.
To create an AMP ad, select Ad type as AMP on the Create Ad page.
Then select the appropriate ad size.
In the Amp Ad Parameters, add the attributes and values that are provided by the ad provider. Below you can check the example for attributes and values.
Below that placeholder and fallback values can be provided.
Now you can publish/update the ad.
Once the ad is created you can display it on the front end in the same manner as you would display other ads, just make sure that the amp ads are displayed only on amp pages.
Create a normal AdSense ad then to enable support for AMP pages you can select the Enable AMP support as shown in the image below.
If AMP support is enabled, the AMP version of the AdSense ads will be automatically rendered on the AMP pages.
If automatically convert to AMP is selected, the ad will be converted to AMP version depending on the ad type and size.
To render it in a dynamic size you can assign a ratio of width and height.
To render it with a responsive width and static height, select the respective option and provide static height.
The preview of the converted AMP code can be seen in the preview box and if needed you can change the code from here.
On AMP pages the views for the ads will be tracked but clicks tracking is not supported.