What makes people feel that you care about them?
Consider having two managers, one tells you frequently “I care about you” but doesn’t act like it.
The other has never said those words but innately you know that is true and if you were to come with a concern you would be heard and respected.
Which begs the question, how do you say “I care about you” with actions?
There is no one size fits all answer.
It means you are thoughtful to that person, their unique preferences and taste.
Going the extra mile, (knowing their kids names, personal interest, hobbies, etc.) showing trust (e.g. flexibility with hours of work as long as work is done, where they work).
The biggest statements are unsaid.