Is it possible to be in christ (be born again)and not enjoy the benefits of being in him?
Yes, it is possible to be born again and not enjoy the benefits of living in Christ; but, I do not know why anyone would want to live that way. It is possible that someone like that has not been taught how to grow spiritually or how to walk in the Spirit.
Paul speaks of people like this as “infants in Christ” (1 Cor. 3:1). Peter exhorts such people: “Like newborn babies, crave pure spiritual milk, so that by it you may grow up in your salvation, now that you have tasted that the Lord is good” (1 Peter 2:2-3).
There are many excellent books and study tools available to assist people in their spiritual growth. The main thing is to get alone with an open Bible, read part of it, and seek God’s face for understanding. It is also helpful to get a mentor. A suitable mentor is someone who has an obvious, humble walk with Jesus. A spiritual mentor should be well versed in the Bible.
By-the-way, the Navigator’s Topical Memory System is a tremendous growth tool. Rick Warren’s Purpose Driven Life is a book every believer would do well to read as it is filled with Scripture and spiritual insight.