Hi @AlfredoCarlos ,
we have two different approaches to this .
1) we have Canvas community sites based on Award level enrolment, which are managed separately to the unit of learning (Canvas Course) so typically Award leaders can email everyone in the Award - differentiation by year group is achieved by creating separate Canvas sections, or sometimes Groups
2) we move the community sites into a Sub-Account sub-structure and use the account level announcements that @ryan_corris mentions. This allows, for example, Bachelor and Masters in a discipline to be messaged at the same time, even though they are in different Canvas Award level courses. We also maintain a School level site for cross-discipline postings on the same basis. - Award level enrolments are fed from our SIS via our middleware.