What I learned about RERA checks after almost making a mistake

Honestly, I almost jumped on a project near Jewar without proper RERA checks. For investors, what's the real way to verify RERA registration beyond just the number for projects like Panchsheel Pratistha? What specific red flags should I look for on the portal? Also, how do you properly check a builder's legal track record, maybe for someone like Real Exchange Group, before investing?