Can anyone help me to model this lever?

Give us a hint at what you want a hint to. We have no idea where you are stuck.

I don't know anything about NX, but I built the model in SOLIDWORKS.
It was actually a little tricky to build, obviously not too hard, but I had to stop and rethink the dimensions, or process in a few places.

A screenshot and a step file are attached.
Maybe seeing it in 3D will help come up with a way to build it?

Here is a photo of the steps I used to develop the model.
No doubt there are other/better ways, but this is how I made the model. If anyone has a better way, then they should document it as well :)

From what you mentioned above, it sounded like you made the revolved bits with their bores. I would not use a revolve feature when an extrusion works. I would also do the bores later as a separate feature. Creating the bores too early make everything harder, especially when dealing with drafted (angled) parts.

General order of making CAD models:
Add material
Remove material
Fillets and other stuff

Try to avoid adding stuff, fillets, removing stuff, adding stuff, fillets, removing stuff... Sometimes you have to do stuff in a weird order, but those should be the exceptions. Follow the "normal" sequence as often as possible.

Yes Fred, I understood very I was doing wrong. Eventually, it clicked. I am attaching my model. I hope it is up to the mark.

Horrible drawing... as usual. Hard to discern how the beam section (6 mm) transitions into the clamping lug (13 mm). One has to make some assumptions.

Also, I don't see a "SR" callout for the 5 mm radius in the top-view (13 mm lug, beam side)... though that would seem to make sense if this were a forging. The draft kinda indicates that it is, but there are some discrepancies...

Okay, so you have some model examples and that's good. Since you're given top and mid-plane diameters, how are you modeling to edit that quickly if the need should arise?