How do I get from El Calafete to Torres del Paine?

From El Calafete, you can take a bus to Puerto Natales, which takes about 5-6 hours including border crossings.

See the bus schedule at https://www.bussur.com/. From Puerto Natales, you can take another bus directly to Torres del Paine. Both buses are operated by the same company - Bus-Sur.