The 7 lives come one after the other, you decide which one you are on based on its characteristics.
This is believed to be your first birth. The first time your soul sees the world. You grow up into a world where nothing makes sense and everything feels new. People in this stage of birth are yet to find their feet. They feel overwhelmed with things and have a low threshold for things they don't understand. Every effort they put in fails and everything they do seems to works exactly the opposite of how they planned it.
This life, being the first, challenges you like life challenges an infant, relentlessly. You need to go through this phase to understand what life would throw at you. This life is led with much difficulty and if you feel that nothing would ever work out for you, then you may be in the infancy of the life chain. There's plenty to look forward to, however. This is your chance to look at the world and start making sense of it so that you are ready when the next stage, ie, the next life, appears.
The learner is the second birth or the first rebirth a person undergoes. Your soul, no longer new to the world, has learned to understand it. You spend this life trying to learn things. Your life is spent in understanding people, emotions, and your personality takes the form of an avid learner.
If you spend most of your time trying to learn new things, trying to understand what people think, how they act and why they do what they do, then you may be in the second life. You not only learn about others but also about yourself. Who you are, what you were meant to do, why you act in a certain way etc. will be some of the questions that will bother you. At this stage, you are not looking for fame and success but your life is spent in learning, in preparation for the one to come next.
The third life or the second rebirth sets you upon a life of exploration. Now that your soul has understood what to expect from life and what are the things you need to learn, your life will push you to explore. You will find yourself attracted to new ideas, new thoughts, new places and so much more.
If you have found the urge to explore overwhelming; if you find yourself looking at places wishing you could go there and if you have this feeling that there's so much to do and so much to see and yet so little time, then you are probably living your third life. Your soul is now looking to find experiences which it can learn from and where it can utilize the lessons from previous lives. This third birth is exciting in terms that you will live it with a curiosity of a child but handle it in a mature way.
The fourth life brings you love. Once your soul knows what it is and what lessons it had learned from the past, it would try to incorporate love into it. You will find love in other lives too, but true love, as we have imagined it, would come in this life. You would have already understood who you are so the next step is understanding who you love and this is the life that'll bring you to it.
If you find that the only thing missing in your life is true love; if you think that you are content with your life except for that romantic aspect which seems to be absent and if you find that day in and day out, all you could think of is finding the right one, then you are living your fourth life. The best aspect of this life is that it will take effort but once you find your true love, it will remain forever. This life would also be an intersection for your partner, who too would be living their fouth lives and hence come into your life to stay.