Its not the first amendment to the canadian constitution (hello manitoba) and the specifics of the rights granted and their limitations are different [sometimes very different than usa. E.g. gay marriage and abortion].

Additionally prior to the charter canada had some limited freedom of speech from the implied bill of rights, so its not like it introduced it.

The Canadian Charter of Rights and Freedoms was inspired by documents such as the 1948 United Nations Universal Declaration of Human Rights. Other international influences included the 1950 European Convention for the Protection of Human Rights and Fundamental Freedoms, and the 1966 International Covenant on Civil and Political Rights. The concept of individual freedoms existed in Canada long before the Charter was put pen to paper, as it inherited its culture from European origins, where elightenment ideals had been evolving since the 17th century. So the Charter and the US Constitution are similar because they are derived from the same set of values.