Brief Answer:
Several excersices

Detailed Answer:
Dear sir, I have gone through your question and I understand your concerns , there are some excersices that can improve your balance but it is important to do them in presence of company and start gradually as not to injure yourself while practicing.. before practicing you need to warm up briefly to prepare your muscles and joints for activity. This can be done by standing up and marching your feet in place for three to five minutes to raise your core body temperature and ready the muscles for exercise. Also do large arm circles as you march if you can do so comfortably without feeling unbalanced
Then raise your right foot slightly off the floor and slowly rotate it 10 times to the right. Reverse direction and rotate the foot another 10 times. Repeat with your left foot. you can do this while sitting and as your balance improves progress from sitting to standing with light support then without support..

Also you can do one-legged stands, Stand behind a sturdy chair, grasping the chair lightly for support. Draw your right foot up toward your left knee. Hold the position for 10 seconds, lower the foot and repeat with the left leg. Repeat for three to five times on each leg. Progress by increasing the duration of each repetition, crossing your arms over your chest, closing your eyes or balancing on an uneven surface, such as a small cushion. This needs to go on gradually and it might take weeks to improve..

Another exercise is that you can walk heel to toe. Move to one end of a long wall. Stand away from a wall just by an arm's-length. Step forward on your right foot. Slowly shift your weight forward and step onto your left foot, touching your left heel directly to the toes of your right foot. Continue walking heel to toe until you've traveled the length of the wall. When you master the basic exercise, progress to walking backward, crossing your arms over your chest, closing your eyes or turning your head from side-to-side as you walk.
For increasing the strength of your leg muscles you can use the following excersice.. Keepyour back straight and your buttocks firmly on your chair, slowly extend your right knee. Hold briefly, then bend the knee and lower the foot to the floor. Repeat eight to 12 times before switching legs and you should complete eight to 12 repeats on each leg.. I highly recommend that these excersices are done in the presence of company and that they are done in a gradual manner. I hope you find this helpful..

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Brief Answer:
Your leg is extended in a straight line parallel to the ground

Detailed Answer:
Dear sir, Hello again..

I meant that you start the exercises with your knee flexed and your foot is on the ground. Then you extend your knee so that your whole leg and foot is in a straight line parallel to the ground and complete the exercise..

I hope you find this helpful...

Regards

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