Hi - the question/issue you pose is why I think promoting Tag Management without a web developer is selling marketers a 'bill of goods'. A web developer's background and expertise is imperative to making it all work. What tag management promoters should tout is that tag management reduces the need for the web developer to modify on-site code all the time. It is still a requirement to know how JavaScript works as well as how query string parameters function, etc.
My opinion listed above doesn't outright answer your question. The answer is that you still need a web developer's expertise to implement the tracking or function you're after. Without seeing your site, the tags you'd like to add, etc., it will be tough to answer with directly useful info.
All the best,
MitchellT
