I have zero programming experience, the most I know is basically HTML. I work in the marketing field which means that I can analyse data but I use excel for this purpose. I’ve seen a job ad that asks the marketer to use SQL, so I want to take some courses on skillcombo.
You can do it! And combining 2 skills makes you valuable.
Lots of free resources such as youtube etc
You not having any programming experience may actually work in your favor because "normal" programming requires "procedural thought" whereas SQL is declarative and requires "set-based thought". Most programmers have a hell of a time making the required paradigm shift to be good at SQL.
To put it in different terms, thing of "procedural programming" as what you want to do to each row one row at a time. Although there are a few more nuances, the first step to making the required paradigm shift to a "declarative language" (such as SQL) and "set based" thinking is to stop thinking about what you want to do to a row and start thinking about what you want to do to an entire column.
A good place to start from "ground 0" can be found at the following link... and, except for you spending a little time understand what's going on, it's absolutely free.
From there, the sky is the limit and you can do some very, very advanced things in SQL without ever having to write a loop (loops are actually contrary to performance in SQL and should be avoided 99.99% of the time).
Since you already use Excel, you already understand "column based programming" because you already know what things like SUM() do on a column... and you didn't need to write a loop to "step through the rows of the column". That's the declarative nature of Excel... as it is with SQL Server.
Also, on the W3 Schools site I provided the link to. Understand that SQL is like English... the basics are the same but it has different "dialects".
Another skill that marketers should have is the one called "courtesy".