Looking for advices and tips (Carretera Austral, Chile)

Hi all!
Soon I will be traveling to Chile (I am Argentine) to take the Carretera Austral from north to south.
How do you recommend packing the bike with bags and other items?
One option is to fly directly to Puerto Montt or to Bariloche and cross into Chile by land. Does anyone have experiences with these options?

I'm not decided yet but I think I'll go with flat pedals and trail-running or trekking shoes. Any comments or recommendations on this?
It is possible that the trip will start in mid or late February, I do not have a deadline but I would not like to exceed more than three weeks. Do you see it possible?

Thank you very much in advance! I am very excited to take this trip.