Hair tips and split ends

I have very weird hair. I'm currently trying to grow it to about halfway down my waist and still keep it healthy as well. I have about 20-25 cm left

Here are two strans of my hair the first one is from behind my ear lobe and the second one is from the top of my head. Why is this happening and how can i make the top one look like the bottom one? Any tips would be much appreciated.