Should I be writing blog posts?
Posting regular articles to your website will improve your domain authority in the eyes of Google which will increase your ranking in search results. This leads to free clicks that can convert with a very low cost per acquisition.
While you'll be creating the blogs yourself (you can outsource this to a VA as soon as they're on board), I would try and get the most output for the least time input possible.
Your highest ROI activities will be signing suppliers, adding products and improving your offer to customers. So your content creation will fall behind this but still worth doing after you have dedicated time towards those primary tasks.
Get your content ideas by checking out the search terms people are using to find your website. You can do this with the keyword planner tool in your Google Ads account.
Then leverage AI to create your content. If you enter the subjects you want to cover into ChatGPT, it can do the heavy lifting for you. Since AI is still in it's relative infancy, there is still debate about how using AI to write your blog posts will impact your SEO (whether you will be penalised). Best practice at the moment seems to be ensuring you include your own original content within the blog post to accompany your AI generated content. The more original content the better.
I'd just set up a monthly goal to start with, perhaps just 1 or 2 blogs so that you can keep it up sustainably. Then scale this when you outsource it.