Exercise can improve balance, strength, coordination and flexibility. So it is vital to keep moving, for example walking and swimming. Talk to your doctor or a healthcare professional about the type of exercise that would be good for you and follow their recommendation. A doctor may refer you to support from a physical or occupational therapist. They can visit you at home to provide an individual exercise program to suit you that improves balance, muscle strength and gait (how you take steps).
Consider joining a local health and fitness centre where you can meet like-minded people and give each other encouragement to exercise regularly. Group activities can be fun. You might benefit from group exercises such as water workouts in a pool or Tai Chi, a gentle exercise that helps reduce the risk of falling. Yoga and body balance classes are also good for posture, flexibility, mobility and balance.
If you prefer to exercise at home, then Age UK has an excellent free guide on simple strength and balance exercises which you can download for free.