Until 30.09.2022, two vaccinations according to the EU-wide vaccination scheme are sufficient to enter Germany. The date of vaccination is irrelevant for Germany.
From 1.10.2022, three vaccinations or two vaccinations and a negative PCR test or two vaccinations and a convalescent certificate are required, which must not be fresher than 28 days and not older than 90 days. There are still numerous exceptions for other conceivable case constellations, including for non-vaccinated persons, who must then remain in quarantine.
Please read all detailed information here: https://canada.diplo.de/ca-en/consular-services/16-coronavirus--covid-19-corona