Answer 1

web dev generally work on back end side , or cloud storage side
whereas designers work only on client side , i.e designs, layout, user interface , graphics etc

sometimes web dev , commonly means , capable of working on both sides(very high level web Devs are commonly referred as full stack developer , being a full stack dev is a huge thing)

I know client side stuffs like html, CSS, JavaScript , jQuery, SVG, bootstrap , etc so it kinda makes me designer ,

but when I ll study , some back end stuffs , like in nodejs or PHP
NoSQLs or SQL
java , c# etc
file manipulation
multithreading etc

then I would be able to call my self a web developer