Hi there! Smart strategy using a blog to drive traffic to your main fanpage! Besides ads and Reels, try these organic methods: cross-promote between your blog and fanpage by sharing blog previews on the fanpage with "read more" links.
Join relevant Facebook groups in your niche and share valuable insights (not direct promotion) - people will naturally check your profile. Use Facebook Events to announce new blog posts, and create polls/questions on your fanpage asking what content people want to see next.
In Ads Manager, try "Traffic" campaigns directing blog readers to like your fanpage, and use "Engagement" campaigns to boost your best performing blog-to-fanpage posts.
Collaborate with similar pages for mutual shout-outs, and always end blog posts with clear calls-to-action directing readers to follow your fanpage.
What niche is your blog focused on, and have you tried joining Facebook groups where your target audience hangs out?