I was told that in order for me to use my llc registered in ny can’t be used outside in another state. Was told to register it as a foreign company in the state you want to invest in. Has anyone gone through this if so how do you go about? 

Yes -

1) find and hire a registered agent (such as InCorp) and pay their annual fee

2) go the secretary of state's website where you want to do business - fill out the form, including the registered agent's name and address in the state.

3) file the form and pay the fee* - sometimes you'll have to wait for acceptance from the secretary of state (Arizona Corporations Commission as an example).

4) be prepared to file another tax return in that state (if that state has an income tax) once you start doing business there.

*Note - in some states, the fees are huge (Texas and California) and it may be easier for you to hold rentals in your own name in those states (be sure you have an umbrella policy if you're worried about liability).

What are you trying to use it for? What is your LLC in NY currently in place for?

what State are you doing business in ? if you mention the State perhaps someone there can help you with that information. If it's PA i can tell you if you sell anything or physically do anything there then you would have to register as a foreign co. but there is a line that says if you only invest and it's passive income, then you do not have to register your co. but everyone will tell you should. best to check a states web site or attorney in the state.