Companies incorporated on or after 2nd November, 2018 have to mandatorily file form Inc-20A for commencement of business on or before 180 days from incorporation date. MCA has mandated every Company (Private, Public, Listed or OPC) which has been incorporated on or after 2nd November, 2018 and having a share capital to file Form INC-20A for commencement of business to ROC within 180 days from the date of its Incorporation.
Form INC-20A is filed to ROC for communicating to government that the company has received paid up value of shares  agreed to be taken by subscribers on Bank account of company and as a proof we have to attaché Bank statement of company showing receipt of money for the value of shares subscribed by each subscribers with Form INC-20A.
Consequences of Non Filing of Form INC-20A within 180 days of the Incorporation.
1.    No company can start its business or borrow any funds until Form INC-20A is filed to ROC  
2.    The company shall be liable to a penalty of fifty thousand rupees and every officer who is in default shall be liable to a penalty of one thousand rupees for each day during which such default continues but not exceeding an amount of one lakh rupees
3.    If ROC does not receive Form INC-20A within 180 days from the Incorporation of the company and ROC has reasonable cause to believe that the company is not carrying on any business or operations, he may, initiate action for the closure of company. 

http://www.mca.gov.in/Ministry/pdf/NotificationCAO2019_15012019.pdf  Dated 14.01.2019  and Section 10A of Companies Act, 2013