I am creating an admin panel for my website. I am coding the entire website by myself. What are some essential security features that I should implement so that only I can access the admin panel and no one else?
The most powerful and simplest security you could add is called mTLS (mutual TLS) combined with Let’s Encrypt for a normal certificate.
With mTLS you create a client side certificate that must be used with each connection initiated, using cryptographicly sound keys.
If you want to learn more about it smallstep have a open source ca and other tools to manage these things.
There are other ways but most offer less security for more work.
Finally any website must be secure from the standard OWASP list like XSS, sql injection l, remote code execution… etc