What marketing basics should a digital marketer learn who is not from a marketing background?

I agree with Mr. Nasir Hussain answer. Thank you.

Brand identification and consistency

Search marketing

Content optimization

Use of Social media for marketing

Sales leads and their conversion

Marketing basic is only to increase the business, to grow the business, to expand the business.So which way you take that depends upon the product and customer that how you may attract them and by that to connect with the com[any or product.