GSTr-3b is the summary return where you're supposed to show all the output and input supplies and make payment payment in case tax on output supplies is more than input supplies.
If you're paying rcm in respect of transportation services , there is an option to claim the credit in the month in which the liability under rcm arose since section 16 talks about supplies 'intended to used for the purpose of business'
Coming to gstr-1 , you are not required to make any payment in respect of gstr-1. GStr-1 only deals with outward supplies and a taxable person is only required to show all the invoices/ debit notes / credit period issued during the taxable period and the tax on such supplies should be equal to the tax liability shown in gstr3 b is most of the cases.