You can either use the paid or accrued method for the foreign tax credit. If you choose to use the accrued method,you can not change back to the paid method in future years.
If you had withholding in India throughout the year and did not pay the total tax when you filed, you may wish to use the accrued method which is reporting on your US tax return, your total tax liability for the India 2017-2018 tax return (not what you paid but the 2017-2018 Indian tax liability). Then for 2019 you would enter the 2018-2019 Indian tax liability for the Indian year 2018-2019 for foreign tax credit.
If you want to use the paid method for foreign taxes, you will need to add up the foreign taxes you paid from January to December 2018 and use that total for foreign taxes paid for your 2018 foreign tax credit.
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