Using my iphone on Wi-Fi in Canada (I'm from the US)?

So I have an iPhone, and I want to be able to use it in Canada. I would only be using it in a Wi-Fi area, so that I can access instagram and facebook and things, not calling or texting or anything.
What kinda of things can I turn off so I don't have messages and calls coming through, as well as data accidentally coming through?
Also, will I get roaming charges for using data in Canada (like internet, not calling) (I have AT&T)?

Put it in Airplane Mode. That's it. Once that is on & remains on you will not be charged for anything. Using Wi-Fi alone will not charge you.

As long as you are using Wi-Fi then you will not be billed for any calls and texts. Your apps and internet, email should continue to work with just being around the Wi-Fi hotspot or in a area that offers free Wi-Fi internet. You have unlimited Wi-Fi internet. If you need a good free texting app, I recommend using heywire. It works internationally as well as domestically for text and it is free. You can use Wi-Fi to use this app as well.

www.heywire.com

Anytime you are using 3G or 4G on A T&T or through their data internet plan or calling then you will be billed for roaming fees. That is why turning on Wi-Fi will deactivate A T&T data internet and so you will not be charged.

If you are afraid of roaming fees, you can contact A T&T customer support and tell them to temporary deactivate your services for the time period you will be in Canada. This way you will know for sure you will not be billed for anything you use. Your cell phone will continue to work when you are in a Wi-Fi area.

Also check out Google Voice. It gives you a free phone number that gives you unlimited calls within United States and Canada as well as texting. You can use Wi-Fi on Google Voice to make calls and text free as well.