I like this sentence, that b: Being with my family for Christmas is the greatest gift of all.

Many Koreans who isare older than my generations were focused on work oin their companies.

You could also say:

Many Koreans from older/previous generations were focused on work in their companies.

In my opinion, the purpose of the works arework is not for work itself, but for becomingto allow me to be happy with my family.

So I am always trying to btreat time with my family as a higher priority than my works.

You could also say:

So I am always trying to prioritize time with my family over my work.

I like this sentence, that: being with my family for Christmas is the greatest gift of all.

Many Korean who is older than mys in the generations before me were focused on work oning at their companies.

As a result, many kids now didn't like workaholic fathers.

Added "now" to clarify that we are talking about the present, and not about the generations before.

In my opinion, the purpose of the works are not forworking is not for the work itself, but for becoming happy with my family.

Not entirely certain what you wanted to express, but I've tried to rephrase it more naturally with minimal changes.

So I am always trying to be with my family as a higher priority thanprioritise being with my family over my works.

I hope my sons will understand my thoughts on this someday.

Best to add "on this" to distinguish that you are talking about your thoughts on work and family, and not your thoughts in general.