Here is a list of some popular sites where you can create profiles creation and potentially get backlinks:
LinkedIn
Facebook
Twitter
Google My Business
Instagram
Pinterest
Reddit
Quora
YouTube
Flickr
It's important to note that backlinks from these sites can be valuable for SEO, but it's also important to focus on creating high-quality, relevant content and building natural backlinks rather than just trying to get as many backlinks as possible. Spamming or creating low-quality profiles and content can actually harm your SEO efforts.