A child referral will include a medical for you to look at. There will also be at least one photo of the child, and often some small amount of history or background on the child. How much information you will get depends on which country you have applied to. Each country is different in the format of referral they provide. You will be given enough information to decide if you wish to proceed.
CAFAC will send you the referral through either your provincial director, or directly to you. How it will get to you is determined by the regulations of your province. With the referral will be forms to formally accept the child. You will be required to sign these and return them to CAFAC office. CAFAC will notify the country and the country representative that you are wishing to proceed.
In most cases this is the point at which the province will also issue a Letter of No Objection (LONO) which states that it has no objection to this particular child, as they have already agreed that you as an applicant are approved.