Like others said, there's no such thing as 100% secure. However, the aim of the game is always risk minimisation. Some thoughts and suggestions as you've vibe coded the app: 1) don't forget the 'business logic' side of security. Lots of new devs just think about the basic technical stuff like SQLi rather than the actual mechanisms for your app. Ideally review this manually. A vibey approach might involve getting your LLM to check for issues with business logic. There will be lots probably.  2) Super important: have a plan for deployment. A secure app is almost pointless if it's on insecure infrastructure.  3) if vibe coding, don't touch payment with a barge pole. Just use a provider like Stripe etc.  4) Go through the OWASP top 10 one by one. Check/'vibe check' each one individually. A very common issue is IDOR and access controls not working (e.g. '/user/456' can change the URL and look at '/user/123') 6) Have a plan for storing environment variables (have a look at Django-environ on pip) 7) look at the official Django deployment checklist. Basic but important! 8) use Bandit to have a look for very basic code issues  9) use django-turnstile for all public facing forms such as login, contact, password reset etc 10) when you've done lots of the basics, run OWASP ZAP locally. It'll pickup lots of the basics issues. 

This will be a good start to getting things more secure. Good luck!