Hi dear,

                  Yes Anyone can be a Web designer if he/she have any kind of degree. Degree doesn't decide a future of a candidate but interests matter.If you have interest in web designing you can do it after BA also. 

Requirement of a Web designer :

Any degree and knowledge of HTML,CSS, JavaScript, PHP, Bootstrap etc. But start from HTML and CSS.

Where to learn from?

You can learn from any online site or online medium such as Youtube. You can also do an online certified course in Web designing from any online course provider platform such as Udemy,Upgrad etc. After completion of course you can get a certificate.

All the best