Hello,

I saw the screenshots you attached.

1) Sorry but the add to cart button is not set to be displayed for the mobile view for the product style that you are using.

You can try changing the product style from Theme Settings >> Shop >> Product Styles.

Screenshot for Clarification: https://ibb.co/NZJqQzz

2) You can edit the content in the footer columns from Appearance >> Widgets.

Screenshot for Clarification: https://ibb.co/Tr6XNdm

3) Please provide a relevant screenshot to check it myself and help you out accordingly.

4) Read More text is displayed for the add to cart button when the product is out of stock. Please make sure that the product is in stock.

Then clear the cache and check back.

Regard’s.
Xtemos Studios.