Hello Clara,
The great thing is you dont need money if you are serious about starting a business from home. you can actually start a website using a free blogging format if you cant afford your own hosting service though I do advice at least buying your own domain name.
think about something you know alot about or would like to know alot about and then start creating content. you can make money with different affiliate programs that are related to the content on your blog.
For example if you are a dog lover, you can create a site about dog training, etc and sale amazon products like dog beds, dog trays, chains collars, etc.
There is lots of information out on the net. do some research