Bilingualism means being able to communicate in more than one language. Children can learn to use 2 or more languages from birth or might learn one language (their home language) first before starting to learn another one.
You can read and hear about other parents' experiences of raising their children to be bilingual in the following resources produced by the BBC's Tiny Happy People.
If your child is struggling learning to use your home language, you may think it will be easier to speak the language that is mainly spoken in the country that you are living in, e.g. English if you live in the UK.