All are acceptable.

Hi Muhammed, Yes, those all sound natural in the USA. Here's a quick breakdown: "Could you please tell him I called." – Polite and formal. "I'll tell him you called." – Simple and straightforward. "Can you just let him know I called." – Casual and conversational. "Okay, I'll let him know you called." – Agreeable and natural.

Yes all acceptable in all English's American British Australian Canadian New Zealand and the rest of the world.