The meanings overlap.
"Secure" can just mean "safe." "I feel safer knowing my money is the bank." "I feel more secure knowing my money is in the bank."
“Safe” and ”safety” are common, ordinary, everyday words. "Secure" and "security" are more formal.
”Safe“ means ”not in danger.” ”Safety” means the condition of being safe.
You might be safe simply because of conditions. "According to the weather radar, the storm is passing to the south of us. It looks like we'll be safe." We didn't do anything. We're safe because we're here and the storm is there.
One literal meaning of "secure" is "to fasten or tie something down." For example, an airline flight attendant might say "Secure your seat belts." Often we secure things so that they won't be damaged. "We use bungee cords to secure our trash cans on windy days." By extension, "security" usually carries the idea of taking an action to make something safe. And it often carries an idea of authority, or something official.