The word "secure" usually means safe. It’s often used as an adjective. Sometimes "secure" means that something is in a good location–it’s not going to fall over or come off easily because it’s properly attached or put into a place.
They feel secure inside their apartment.
This part of the city isn’t a secure location for raising a family.
This door is not very secure. It’s wobbling and it might fall off.
The state needs a secure facility for housing prisoners temporarily.
Move that box. It doesn’t look secure.
A secure website provides you with protection from having your data stolen.
https = hypertext transfer protocol secure
When you use "secure" as a verb, it means to get:
Robert was able to secure a second job.
Aleah will need to secure a loan from the bank to start a business.
They need to secure housing for the winter.
As a noun, "secure" changes to "security."
Laura’s sense of security was shaken after thieves broke into her apartment.
Call security. Someone left an unattended bag in the airport terminal.
This building has good security.
The word "security" can also be used as an adjective:
Our store has a good security system.
The apartment building has all the latest security features.