Your body is a mere accumulation of food, your mind is mere accumulation of memories. No flesh defines ‘you’, nor any structure of your mind, u yourself can change entirely.
I am this or that is a self-identification. U don’t need to think about other incarnations, the rest of you that is not accessible to you at the moment in your everyday life, therefore I am this human structure is sort of an approximation. Just bcs some parts of u may not be accessible to you atm doesn’t mean that it isn’t you.
We just are. We are beings and human form are our characters, our chapters. Your human you is not the absolute you.
After death, you lose your discriminatory mind, you lose your sense of who you are, and will just merge with the rest of you, but you ultimately stay you.