AMP in Default Theme

Can you please follow this tutorial?

Tutorial: https://ampforwp.com/tutorials/article/how-to-make-your-theme-compatible-with-amp/

Ok
Thanks

Do I need to add AMP Plugin ?

Yes. you need to add an AMP plugin.

After adding the plugin how can i select front page default ?

I have added Plugin & set the Home page but some script is not working.
I have sticky sidebar in left but it’s not working.
https://cochranlaw.com/meet-our-attorneys/?amp

Can you please tell me how did you add the Left sidebar on your website?
Like this: https://monosnap.com/file/w36P42itHj2INfDNdMrH7sLG3ia1nL
On your Non-AMP page, it is sticky. So you need to add some custom scripts in AMP.

Can you please follow this tutorial: https://ampforwp.com/tutorials/article/how-to-add-custom-scripts-in-amp/