Do I need to add a comma before an "and"?

Solution 1:

Yes and no. Generally you include a comma after every item in a list, and the sentence above would qualify. In that case, the comma would be referred to as an Oxford comma. However, a case can be made that you don't necessarily need a comma before and. It really depends on what style of writing you're using, whether or not you're submitting it for a specific task and whether or not they accept it, and/or if it looks right to you. Honestly it depends on any of those criteria.

https://www.grammarly.com/blog/what-is-the-oxford-comma-and-why-do-people-care-so-much-about-it/