Hi knopko,
Welcome to the Apple Support Communities!
It sounds like you would like your Megafone iPhone to relay the SMS messages it receives to your Apple computer Messages application. If this is the case, please use the attached for instructions on setting up this feature. If I have misunderstood the question, please let me know.
Connect your iPhone, iPad, iPod touch, and Mac using Continuity - Apple Support
- Your iPhone, iPad, and iPod touch need to use iOS 8.1, and your Mac needs to use OS X Yosemite.
- Sign in to iMessage on your iPhone, your other iOS devices, and your Mac using the same Apple ID.
- On your iPhone:
- Go to Settings > Messages > Send & Receive > You Can Be Reached By, and add a check to both your phone number and email address.
- Go to Messages > Text Message Forwarding, and enable the device(s) you would like to forward messages to.
- Your Mac, iPad, or iPod touch will display a code. Enter this code on your iPhone to verify the SMS feature.
Cheers,
Joe