Is it considered a lie or a sin for a person to provide false information (such as age, date of birth, or name) when creating online accounts (such as Google, gaming, or websites)?

It is not obligatory to provide real information when creating an account on websites, unless it involves the rights of others, such as in buying and selling transactions. In such cases, it is necessary to provide the real name and perhaps age. Otherwise, there is no harm in using a pseudonym and an untrue age.