Congrats on taking the first step.
You're probably feeling overwhelmed, so the first thing I want you to do is to take a step back. Before you even think about marketing you need to get your store set up, you need to have a plan, and most important you need to have some goals.
Your Store:
- Have you set up your theme?
- Is the branding uniform throughout the site?
- Does your branding match your niche?
- Did you design a custom logo?
- Did you add all the required plugins?
- Did you add the TOS/Privacy Policy/Refunds pages?
- How will you add products? Manually or Oberlo?
- Do all your products have edited titles and descriptions?
- What about edited pictures?
- Would I buy from this store?
You can keep adding questions to list forever, but these are the core questions to provide a minimum viable product.
Your Plan:
- What niche will you choose?
- What pricing strategy will you choose? High Margin or Low Margin?
- Will you do Free + Shipping?
- How much will you charge for shipping?
- What will you implement to boost conversions?
- How will you recover abandoned carts?
- Will you build out social media profiles?
- And on and on...
Your Goals:
- Given my profit margin of X, I would need to sell Y per day to make Z
- And on and on...
Most of the questions above can be answered by typing "How to ____" on Google or YouTube.
Once you have your store ready, that's when you're able to start thinking about marketing and Facebook Ads. For more information on that, it's as simple as YouTube or the handy-dandy search feature in the top right-hand corner of the forum. If there's anything you want to know, you can use that to find it. If you have a specific question on something and you can't find an answer, then make a thread and ask the community.
I hope I gave you some ideas about what you should look for.