The types of investments that can be held in registered savings plans – like Tax-Free Savings Accounts (TFSAs) – can be found on the Canada Revenue Agency’s website.
There are no limits on the percentage of foreign investments that can be held inside a TFSA, however you may be subject to foreign tax depending on the investment’s originating country. You may also trigger a tax event when you transfer the investments. Learn more by reading this previous question.
Speak to a financial advisor or tax professional to confirm whether you can hold the investment in your TFSA, and to learn about any tax you may be liable to pay.