Any weight bearing exercise can help you ward off the effects of menopause. This can help delay the process of bone density loss. Brisk walking is one way of achieving that, which works on your cardiovascular system. To add to this, you should do some muscle endurance exercises, either using weights or free-hand exercises like push-ups and squats to strengthen the muscles.
Make sure you work out ALL parts of your body equally so there is balance. Along with this, you might like to ask your doctor the benefits and risks of HRT as well as taking calcium and vitamin D supplements. Also, visit your gynaecologist to check if there is some other cause of cessation of menstruation.