Power of attorney

I am a single senior citizen lady, 65 years old. I do not want to leave my property or savings to any of my relatives. My parents are no more. I have a flat of my own and have inherited a bungalow from my parents, who have willed it to me, but the will is not registered. I have not sold the bungalow so far and have been advised to wait for some years. My 2 siblings are independent, married financially very sound but expect money from the sale. My questions: 1. How can I legally nominate a friend to look after my finances and property in case I am unable to do so while alive? 2. How can this friend legally help me in case of bad health, without being challenged? 3. How can I distribute my finances without being cheated by my friend while I Aam alive? 4. What legal steps can I take to make me financially safe ? Since I have to give my operating rights of my accounts to a friend. 5. Will a power of attorney help the friend to function in case I need medical assistance and I cannot take a decision or in the event of my death ?