Sorry not from NY, but make sure you read your state board reqs carefully and if it is not clear if internship experience would (or would not) count or how many references/PEs you need to signoff, give them a call or email for clarification.
WWW.op.nyses.gov/Prof/pels/performs.htm
I could give you PA reqs, but it won't help you since each state has different reqs.
As far as what to put on the app when describing work experience, put yourself in the review boards shoes....what you write needs to provide enough details for them to confirm you have been working as an engineer with increasing levels of responsibility.
It is usually a good idea to be very descriptive in describing what you actually did in your job. Don't use vague terms like: worked, reviewed, assisted on such and such project. Rather be specific with what YOU did. Calculated, designed, etc. Adding the how you did it helps too citing methods, specifications, regulations.