Is congenital heart disease correlated with age? are older people more at risk with congenital heart disease, if so, how can it be prevented?

Congenital : Congenital heart disease is a broad category that includes all heart conditions that are present at birth. Some are quite minor, but others are very complicated and associated with very high risk throughout life. Generally, cardiovascular conditions are associated with increasing risk as people age and this is also true of the congenital heart conditions. Also keep in mind that people with congenital heart disease are also at risk for acquired heart conditions like coronary artery disease. In the modern era, it is increasingly common for people with complicated congenital heart disease to live long and full lives. The best thing to do to prevent problems later in life is to see an expert in the care of adults with congenital heart disease. These experts are typically located at large referral centers, such as university hospitals.

No: I think this is a definition issue. Congenital means "from birth", and most congenital issues are caught nearer to birth, especially major ones that either cause blue lips and gums, or failure to grow properly. Sometimes an issue like a small hole between chambers of the heart goes undetected, and is found later on a cardiac work up for other reasons. But issues like that start from birth.

No: Congenital means "present at birth". So an adult cannot "develop" a congenital heart defect.