Buying low-quality backlinks is not a good strategy for long-term success in SEO. Instead, focus on creating high-quality content and earning backlinks naturally through outreach and guest posting. You can also use forum links, but try to make sure they are of good quality: niche-relevant forums and threads, without the direct presence of spam in the subject.
Building a strong social media presence can also help to increase your brand visibility and attract organic backlinks. Remember, quality over quantity is always the way to go.