Gambling activities in Canada are governed by the Federal Criminal Code. Section 201 and 206 make all types of gambling, betting, and lotteries illegal with limited exemptions. Companies are not granted licenses, but rather are registered at the provincial level to provide gaming services. Although there is no legislation or case law that especially prohibits online gambling by private companies, it is mostly believed that it falls within the prohibitions defined by the criminal code.
For more details, check this article: https://iclg.com/practice-areas/gambling-laws-and-regulations/canada