Take the inventory of what you have - skills, items, acquaintances.
Start asking for help. The worst people can do is to say 'No'...
First and most important thing: where are you going to sleep tonight?
A public shelter, a church, a train station, a car, a friend, a police station.
Food: in the worst case, you can go without food for a few days, but not without water!
Ask discretely for a glass of water in any small businesses open to the public. General shops, coffee shops, restaurants, etc.
In most public buildings there are water taps available to visitors!
Personal Hygiene: this is a deal breaker because nobody wants to deal with dirty and smelly people.
There are free ways of keeping clean. Public bath houses. Public toilets, at very early or very late hours, usually. Large petrol stations with free facilities for truck drivers. A spring or a stream when it is nice weather. The public showers on a beach.
Step over your ego and ask for a bit of change from people around you. The most likely to give you some are the couples. Whatever you get save it until it becomes a bit more consistent.
Start offering your help to strangers that may benefit from it! Those carrying heavier items. Market sellers/shoppers/staff. Small business owners. Do it every day, from early morning. If anybody offers to hire you - even for a small income to you - go for it!
In most countries you can volunteer for work at charities that will offer you meals in exchange for your efforts. Religious centers usually offer regular 'free meals'.
Offer your services to wash cars, shop windows, mop or brush in front of buildings, and any other menial job that may be available. Ask to use their equipment if you don't have any.
Reality is that unless you act, it is very unlikely to get any help.
And at times there will be situations when somebody else may benefit from your help - and those are the opportunities for you to help yourself.