Processing timelines.

certification of school transcripts.
Registration with CGFNS
Registration with a state board of nursing.
Registration for NCLEX RN exam.
Take and pass the NCLEX RN.
Start of the immigration process.
Green card application (Form I-140) 3 months to approve
Visa screening by CGFN
Application moves to National Visa Center (NVC) for processing
NVC welcome letter received, Fees paid.
Form D260 filled and supported documents sent to NVC.
NVC complete and set interview date with local USA embassy.
Complete interview and medicals, Green Card issued.
Travel arrangement complete and relocation date set.
This is how the process work, and the timeline is 6-9 month when your application of I-140 received and please this is guesstimate according to USCIS.gov