thats almost like saying do you think people who have never been parents, can make successful parents. You learn everything by experience, you'll get better and better at being a parent, or foster parent.
All children need the same things really, someone to listen, someone to care, somewhere to feel safe and secure and loved. I expect you remember the things that were important to you in your own childhood.
Being a foster parent is very rewarding, there is lots of support, and it can be hard work.