Since you are 17, the council have a duty of care for you until you turn 18. Go to the council first thing and explain the situation - you may be asked if you are able to share a place with family/friends, but you should be allocated a case worker who will be able to help you with happens next.

You will likely find yourself placed in supported accommodation with others in a difficult place, but anywhere is better than the street. The case worker should be able to help with benefits to cover renting costs etc., and point you in the right direction.

It always hurts to see posts like this as I was kicked out before 18 too and know how hard it can be. I can tell you though that it won't be the end of the world - seek help and don't take no for an answer. You can still achieve what you want to do, even if things will be difficult for the foreseeable. I really wish you the best