I'm sorry to hear of your situation. Are you living in the UK?
Are you looking to have someone live in and care for you permanantly or would you be happy with having someone visit you a few times per day?
I'm no expert in Visas, but I guess your friend would need to apply for a student Visa, which would allow him a certain amount of time here. He would have to prove that he's actually studying here, by providing proof from a college or University. When I had a cleaning company around 6 years ago, most of our cleaners had student visas, which allowed them to work up to 20 hours per week.
My mother is 83 and lives in Warden assisted accommodation, so she has her own Bungalow, with intercom. She doesn't want to live in a care home, but her doctor recommended Social Care, so she has carers who visit her three times per day. They aren't there for long, so don't provide any kind of company as such, but all her meals are prepared for her, some cleaning and washing is done and they assist her with washing and dressing in the morning.
Perhaps this is not what you are seeking, but there are agencies that can also provide live in carers too.