That depends . The type of hernia can dictate what you can do. There are many patients with hernias who work out on a regular basis with no problem. If you have symptoms, however, you should see a doctor asap.
Probably. In order to answer this question, i would need to know the location/type of hernia, it's size, your health (and size), and your symptoms. In general, if it is small and not affected by exercise, you are probably ok, although it may lead to the hernia getting larger. Your safest bet is to see a hernia surgeon and ask them their opinion--words cannot replace a careful physical exam. Good luck!