It depends a lot on the niche of your subs. There is no single strategy that last long and they are in constant evolution. If you go to Udemy for example there is a ton of under $20 FB Ads courses that may give you some insight if you are completely lost. But it's unlikely you will find a case use that fits exactly your monthly subs.
But personally I don't think there is any single killer course. The key for me is clearly focusing on the TOOLS. Which tools? First the Ad Tracker. This is omega-key. Then the copy and the ad creation process rollers like AdEspresso which may save you a ton of time for A/B testing and segmentation testing. And the king of all tools, an Ads Spy to see ads that will be similar to your product. For example I recently saw an add for a monthly recurring product, that was plain killer. But the video production was very neat, a couple of thousand bucks spent on that sh*t. So in this case, you will also need to learn on how to produce such quality videos, or prepare a good amount of money.
I don't know if there is a single course that analyses all of this, but for me this is a discipline that goes beyond just FB Ads or Google Ads, but ALL kind of ads, including native, popads, .... so basically this is the CPA learning topic.
Here you can find this specific topic covered:
https://www.blackhatworld.com/forums/cpa.50/ although this forum doesn't focus on CPA 100% and I cannot recommend you anything for this, because it doesn't abide the rules here.
TL;TR: I would not trust a single FBAds course. It will 100% insufficient, although checking the official docs as
@BlogPro is a great head start.
Anyway, if you insist on buying something, check Chase Chappell course (check his free content before to see if it fits you)
