There is no general age limit. The minimum age for playing in real money games is 18 years. For free games, it's only 13 years, but these require parental consent. Since many players are minors, the casino reserves the right to ask for proof of your age before you can withdraw any winnings.
Children may only play with parents' or guardians' permission and must wager the money they receive from their parents or guardians. Parents of children are liable for all activity on the account, including deposits, withdrawals, and wagers made online.
Please visit the following page for a complete list of countries where age limitations are enforced: https://www.comeon.com/en/help-center/faq/age-requirements.