My heart beat is showing 90 in rest and 130 after execise in an oxymeter . can i reduce this at home without consulting any doctor and medications ?

Improving your general health and muscle strength can reduce resting heart rate. Elite athletes can have a resting heart rate below 50. However, it would be prudent to get checked by a doctor before engaging in strenuous exercise. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs.

It is normal for the heart rate to increase with activity. It is never a good idea to treat yourself even if you have medical knowledge. It is dangerous if you have no medical training.