Non centered image alignment

hi! is it possible to align images not centrally but like in this post for example:

This is a ghost blog, it should be possible somehow. And is it possible to add hover effects to posts? Like when you point a mouse to image text appears. Internet is full of samples of how you can do it with CSS and HTML, but I can’t understand how this functionality can be added to posts. Can someone point me in the right direction? Thanks!