These are garment measurements.
for eg: if your chest measurement is 36, the size that would best fit you is a medium (m). 3 inches to 4 inches Ease.
The Sleeve length & Kurta / Dress length vary within styles. these measurements will be listed along with the style descriptions.
For Blouses, if the kurta size you are wearing is M size then you need to select M size for blouses as well.
These are the ready measurement for Garment.