iOS 10 SMS on to iPad?

On the iPhone, Settings>Messages>Text Message Forwarding. Both devices have to be on the same wi-fi network, and you will have to enter a pin when requested.

Set up SMS and MMS messaging

Use this feature with any Mac, iPhone, iPad, or iPod touch that meets the Continuity system requirements. Make sure that your devices are set up as follows:

• Each device is signed in to iCloud with the same Apple ID.
• On iPhone, go to Settings > Messages > Send & Receive. Make sure that the Apple ID at the top of the screen is the same Apple ID that you're using for iMessage on your other devices. Add a check to your phone number and email address, so that you can be reached by iMessage at both. Do the same on your iPad or iPod touch.
• On iPhone, go to Settings > Messages > Text Message Forwarding, then choose which devices to allow to send and receive text messages from this iPhone. A verification code then appears on each device. Enter that code on your iPhone.
• On Mac, open Messages, then choose Messages > Preferences. Click Accounts, then select your iMessage account. Make sure that the Apple ID shown here is the same Apple ID that you're using on your other devices. Add a check to your phone number and email address.

You're welcome.

I did all this steps, but when I chose my iPad, there is no code on iPad and the iPhone is waiting for that code.

Hi. You may need to turn on Bluetooth on both devices.