In your research, I recommend staying away from blogs because they won't be able to give you academic information unless you are looking for personal relations between people and social media. The blogs can be very triggering to someone with an eating disorder. I also would be careful of websites you find because most dot-com and dot-org websites will be organizations talking about treatment methods and offer ads about treatment groups. Rather than using dot-com and dot-org websites, I would recommend sticking to edu websites because they will most likely less bias information and have more trustworthy sources, but make sure to always check your sources when researching on your own.
If you are researching specifically Anorexia you should also research deeper into body imagines because most people will develop eating disorders like Anorexia through warped body image. I suggest using words like "Body image" AND "Social Media", they will give you results on how social media can affect a person or a child's self vision of there body.
When researching this topic you need to beware of pro-ana sites. These sites are very bias towards the "good" things about anorexia. People on these websites or chat boards will defend their actions and thoughts about the harmful eating patterns they put themselves through. I recommend everyone to stay away from these sites because they can be very triggering to someone with an eating disorder. Also, these sites have no academic information and can be harmful to people's mental health.