Need a relationship table.
N:N (Many-to-Many): A table relationship that depends on a special Relationship table, sometimes called an Intersect table, so that many rows of one table can be related to many rows of another table.
When viewing rows of either table in a N:N relationship you can see a list of any rows of the other table that are related to it.
Reference:
https://docs.microsoft.com/en-us/powerapps/maker/data-platform/create-edit-entity-relationships