How to carry out cyclization of 1‐(2‐methylbutyl)‐2‐nitrocyclohexane?
The Hofmann-Loeffler-Freytag reaction as suggested by @user55119 in the comments above is the way to go.
First you need to reduce your nitro group. The reduction of alkyl nitro compounds is less simple than aromatic nitro groups and lower yielding in general. I would suggest the use of Al/Hg amalgam.
Acetylate the resulting amine.
N-chlorinate the amide - trichloroisocyanuric acid is good for this conditions
Irradiate the chlorinated amide to form the [5] ring similar to this example Baldwin gelsimicine synthesis
Finally hydrolyse off the acetyl group with cHCl.