Paulo Perdu is a great instructor, his course will give you not only the fundamentals needed to succeed as an super affiliate but also the mindset you need. Also, Paolo is very helpful as in instructor giving you advice, tips and the tools you need to succeed IF you put in the work yourself. Nothing in life is free, but this is as close as you can get success for.
If you have built up an email list, you could also promote your affiliate offers via email promotions. Just make sure you build up a relationship with your audience first instead of going for the hard sell straightaway. The emails you send out must contain your affiliate links to products so when your audience click through. the sale is attributed to you.
As for your question about which affiliate program to join, I cannot give you an answer for that because that’s totally depends on the niche you’re in. I’m not familiar with your niche so I can’t give you any recommendation for that. That’s for individual private affiliate programs. You can also check out the common affiliate networks like Amazon, ClickBank, Shareasale, CJ, all these.
A more complex system, pay per lead affiliate programs compensates the affiliate based on the conversion of leads. The affiliate must persuade the consumer to visit the merchant’s website and complete the desired action — whether it’s filling out a contact form, signing up for a trial of a product, subscribing to a newsletter, or downloading software or files.