Hi,
It would be really helpful for us if you could elaborate your requirement, so that we can give you the specific solution.
As per your query, I am thinking that you wanted to create a task after the completion of process.
If this is the scenario then you need to create sub-process to do this, please follow below steps-
1. You can create a main process where you have to create two activities(may be more as per your requirement).
2. One first activity you need to use sub-process(i.e Type as Sub-process) where you have to plug/use your current process(assuming that you are having a process where task is assigning to the user(s)).
3. Then after this you have to use another activity("manual" as per your requirement) where you can create/assign the task to selected user.
Here the actual flow is like a main process is triggered and assigning task to the user. After completion of this task sub-process will be completed and it will return to the main process. Then again you can assign task to the selected user(s).
Hope this will helps you.
Kindly let us know if you are having doubt or if I misunderstood you requirement.