in the erpnext i want to add validation according to the above file. in this file there is 3 price section with their quantity which is 1-1000 sq meter, 1000-10000 sq meter, 10000-25000 sq meter, so if i put 800 sq meter quautity it will automatically fetch the price from 1-1000 se meter, and if i put 6000 sq meter quautity it will automatically fetch from 1000-10000 sq meter.
You can achieve this with a group of quantity based Pricing Rule. It is a very power but configuration-heavy exercise. You’d have one Pricing Rule per quantity range, which in your example who be three: 0-999, 1000-9999, and 10000+ (setting only the min qty and leaving the max qty empty).