Mysql Aurora limit sessions

I am checking my databases, I have 2 with Mysql Aurora and one with Mysql Community. In one of the Aurora databases, the activity is measured in “Sessions”. According to the definition in the documentation, it is a connection to the database and it performs a query, but in the column “Current activity” it shows 0.30 sessions.

What does this value mean, as it is different from the connections shown in the other database.

How many maximum connected sessions can my database have? Is it possible to increase the number of allowed sessions?