Everything you're describing is textbook small-team marketing. With five people, roles blur fast, so of course you're touching social media, lead gen, sales, and a dozen other things at once.
Here's what I'd actually do: stop trying to "master marketing" as a whole. Sit down and answer three things on paper - who the ideal customer is, what problem the product solves, and why anyone would pay for it. Write it up as a simple one-pager and keep it somewhere the whole team can see. Once that's locked in, content and lead generation get dramatically easier because you actually know who you're talking to.
The lack of company material for social is a non-issue. Customer questions, common mistakes people make, behind-the-scenes work, case studies, lessons learned, even stuff you're figuring out yourself. That's all content, and honestly it performs better than polished corporate fluff.
One thing worth internalizing early: with a high-ticket product, volume is a vanity metric. A handful of relevant prospects beats thousands of random followers every single time.
Also, cut yourself some slack. Learning marketing while doing the job is brutal at first. Pick one channel, one audience, and one measurable goal for the next month instead of trying to fix everything simultaneously. Trying to fix everything at once is exactly how you end up fixing nothing.
