Controlling parallelism on Terrasoft.Core.Tasks.Task.StartNewWithUserConnection

Is there a way to control parallelism when using Terrasoft.Core.Tasks.Task.StartNewWithUserConnection (see documentation here: https://academy.creatio.com/docs/8.x/dev/development-on-creatio-platform/back-end-development/data-operations-back-end/execute-operations-in-the-background/examples/register-a-background-operation )? The documentation doesn't mention it, and I don't want to overload the system or having the system spend too many resources on running a lot of these background tasks at once, but also want to be able to run them sufficiently in parallel to give performance boosts to a large task that needs to be performed.

I would also like to know if there is any way to check for task completion if possible, but it seems like these methods do not allow it - maybe I am missing something though?