Hi @Saleh_Alnaggar, displaying different content to different viewports falls under Web Development skills rather than Magento. I think the simplest method is using CSS. There are probably better methods, but I don’t know what those are.
Unless you’re saying that you already know how to do this, but you want to learn how to implement those skills within a Magento Theme? If that is the case, then you’ll need to learn and understand the basic fundamentals of Magento 2 Frontend Development in order to move forward.
References:
- Your First Multi-Device Site by Google
- Frontend Developer Guide by Magento
- Official Magento Documentation (Compilation of courses)