How to connect tasks from different boards

Hi everyone,
I am a newbie. I want to understand how i can connect tasks that are in different projects. Example: i am creating a board called marketing activities and another one called content creation. Some of the tasks belong to these 2 projects and i would like to connect them. How can i do that?

Thanks,
Ana

Have you checked out linked columns and mirror columns? It may make sense to have a master board and then then down to the other boards.