If your niche doesn’t allow you to promote or build premium products (anything over around $100 per unit) then think about getting a solid mix of offerings and building it up over time. I remember Darren Rowse saying that initially Amazon Associates was a really small source of income but over the years it has really started to add up. Think eBooks, affiliates, consulting, books, etc. and you’re starting to build an income stream.
If you want to really make money with your blog, you need to create a mailing list using one of the billions of email service providers out there. I use and love ConvertKit, but if you are just getting started and don’t understand sales funnels, sequences, or tagging you might want to start off with something simpler and free. If that is the case go with MailChimp where you get the first 2,000 subscribers free or Mailer Lite.