Hey Anshuli,
Create a column as below,
Column = ROUND(SUBSTITUTE([COLUMN NAME],",",""),2) or INT(SUBSTITUTE([COLUMN NAME],",",""))
The above code would first convert a number with, into a number form such as 1,20,344.7354 -> 120344.7354 Then use the round function to round to n decimal point form. int function would round to its nearest number without taking value for n.