Is "I'll call him ten minutes later' correct?

I'll call him in 10 minutes.

You might say "I called him 10 minutes later" when both the call and the event 10 minutes before were in the past.

Depends on the context. If, say, you know you'll learn something by noon tomorrow and want to convey the answer to him, you'd say "I'll call him ten minutes later.", i.e. at 12:10.

If you mean you're going to call him in ten minutes from right now, you'd say, "I'll call him in ten minutes" (NOT "ten minutes later").

As you've seen, Ms Tan, English native speakers don't use 'later' like this in this type of situation. Perhaps it's a direct translation from your own language and it seems natural, but it isn't.

Japanese speakers also make this "mistake".

We also use "___ minutes/hours/days/weeks/months/etc. from now".

Thanks, Jack and JTT.