Hello,
I am a 36 yr old female. I have itching in my scalp and hiar loss. Itches mainly where I tie my hair.. but little at the back as well. Its too itchy and bruises are also there. In the front I have thinning hair. Please advise how to stop itchin and reduce hair loss. My hair gets oily soon

Nobody online can provide anything meaningful. You would have to be examined by a dermatologist and have them do test to determine what of numerous possibilities woud be most likely.

You may have an infectious kind of seborrhea. Do some research on those words. You may also be deficient in nutrients. What is your diet like? And have you given birth?
Much as I don't like anti-bacterial soap, try some (hand soap) on your hair for about a month. You don't need a lot, but massage your scalp with it for several minutes while you are in the shower. Leave it in for as long as you can before rinsing. And wash your hair more often, before it gets so oily. Use a good name brand like Bath and Body Works.

If you really have bruises and not red bumps, then see a dermatologist ASAP. That makes no sense. If they are really little red bumps that ooze oil when you push down on them, that's a kind of seborrhea.