Hey Sergii,
To do this from LabVIEW, you can use the Sequence.GetNumSteps and Sequence.GetStep methods. Here's an example:
After opening the sequence file, you can see the GetSequenceByName method, which I used to get a reference to MainSequence. Then, I used GetNumSteps with StepGroup_Main as the parameter to get the number of steps in my Main step group. I then used the GetStep method to get the reference to a specific step within the Main step group, and for this example, just accessed the name of that step.
In a real application, you would likely want to use a loop, where you use GetNumSteps to know how many times to iterate the loop, and use GetStep to get a reference to each step. Also, the code here of course is not complete--all references need to be closed once you are finished using them.
I hope this helps, and let us know if you have any further questions!