Yes, ofcourse, international students can buy stocks in Canada. They can open a brokerage account, trade stocks, bonds, etc.

Follow the steps to invest in the Canadian stock exchange market: Firstly, you need a SIN to open a brokerage account. 

International students can also apply for SIN with a valid study permit to work part-time during their studies.

Step 2: Find a brokerage firm that suits you. In Canada, many online brokerage firms provide trading and investor services.

Step 3: Open your brokerage account with your selected firm. To open an account, you have to provide identification documents.

Step 4: Transfer funds from your Canadian bank account to your brokerage account or use another method mentioned by the brokerage firm.

Step 5: Do research on stocks and other securities that you wants to purchase. You can check financial news, market data and other resources to make decisions.

Step 6: Once you decide to invest, you can buy or sell orders using your brokerage account. Trades will be based on the market conditions of the Canadian stock exchange.

NOTE: Investing in the stock market involves risks, so please educate yourself before investing or take advice from a professional.

Maybe tax rules apply to your investment, so please review the tax regulations in Canada or consult a tax professional.

Remember that the regulations and requirements may differ, so please check with a selected brokerage firm or consult with a financial advisor.