Hey Oshani

try this simple standing pose (Tadasana or Mountain pose)

this helps to correct posture, improve breathing, relieves back ache etc

focus on making this a routine thing...

Mountain Pose (Mountain pose)
Stand upright, feet hip width apart, toes turning in slightly
Strengthen the legs, tuck the buttocks in
Lift the chest, release the shoulders down
Lengthen the spine
Relax the face

hope this helps

xx yogababy