Chemo and hair

Hi I’m due to start chemo and Imunetherapy for my stage 4 metastatic lung cancer spread unit bone I’m worried about loosing my hair and read that I should get it done before I start treatment but the nurse said I probably won’t loose it just thin maybe but I don’t want to walk about like that and she didn’t seem very helpful just said oh we don’t do that! Please can you help on this matter thanks Mel