OK, you're on the standard dual band ham radio. There should be several repeaters around for you to talk on. This may be a good place to start in finding them (Somerset County, New Jersey (NJ) Scanner Frequencies and Radio Frequency Reference
). Ignore the D-Star since your radio won't work there. Also ignore the NJ-TRBO Linked Amateur Radio Network for the same reason. Program in the 2m and 70cm frequencies and include the tone required for repeater access. You may want to verify both the frequency and tone by searching for the repeater(s) in question to make sure you have the most current information as they can change without notice (the repeater's owner's web page is probably the most accurate).
Next, don't try to transmit or call CQ right away. Listen to them for several days to see how those repeaters work. Some have a few users that monitor nearly all the time while other users are only there during the typical drive times. There probably are also nets that are designed for specific purposes and topics outside of that purpose are generally not welcome. Also some nets are closed to authorized users (only club members, only RACES members, or the like) while others are open to everyone. For the open nets, listen closely for how they wish users to check in and when the various types of users are to check in. That may be by members vs. non-members, by location, by type of station (low power, short time users, etc.) and check in as appropriate. They may wish for you to say your call sign normally (just the call sign), say it using the phonetic alphabet (Alpha for A, etc.) and may or may not want other information, such as name, location, etc.
Some groups welcome new users easily, while others are not as welcoming. You can often join either type if you do lots of listening to get to know the folks, topics, and how they operate and after monitoring for a long time (some think it's a way too long of a time) and during a pause, give your call and state you have a question, comment, or other appropriate thing to add to their conversation. Just make sure that your question, comment, or whatever is on topic and appropriate with how the group normally talks.
Be aware that you are not a member, friend, or much more than a tolerated guest initially so be careful about how you handle yourself. After a while they'll get to know you and accept you as a part of the group and then you can join in on some of the less formal conversations (joking around, friendly name calling, etc.),
Many repeaters are owned or at least sponsored by clubs so it is highly recommended that you attempt to attend one or more of the local clubs. That will allow you to actually meet the folks and give you a head start on being accepted as part of the groups and conversations. This may be one in your area http://www.qsl.net/scars/
Some of this may sound petty and cliquish, and quite frankly some is. But you must remember that often the long running groups on the repeaters have had their share of folks who have only one goal, and that's to disrupt the conversations so those groups often do make it difficult for folks to join. If you put in the time and effort to many of those groups it will be well worth it though.