I'm a newcomer to this forum, although I've watched it for years. In the past (though to about 2012) I just booked and flew what I needed for work-tourism, without considering much miles, cards, lounges, etc.
Now I have a new challenge.
Background
I'm booking an Antarctic cruise starting with overnight in Buenos Aries on 25 Nov. 2024, and returning 12 Dec. 2024. This included a charter to-from Ushuaia.
I also have a new almost empty Miles & More card.
I've never been to South America nor ever taken a cruise.
I need to leave Luxembourg and arrive in Buenos Aries before 25 Nov, and then get back after 12 Dec.
But around that fixed period I have plenty of time to enjoy the trip and add some additional tourism.
I will travel business class, and want to take my time and enjoy the total experience.
So my questions.
What is the best business class flight from Europe to Buenos Aries?
I can fly to a hub, or drive (with overnight airport hotel). The long-haul can start in Amsterdam, Frankfurt, Paris, Brussels, Zurich, or even London.
I could consider a vacation stop-over before-after the long-haul, and that could be anywhere in the world, e.g. London, Dubai, Singapore, etc.
I would like to build miles on a card, with my new Miles & More, or I could open another card if more useful.
I might even consider taking out a new debit-credit card for the trip if advantageous.
I expect to travel quite a lot in the next few years (recently widowed) so I want to make the right decisions now.

I'm out of my comfort zone, and I will certainly have more questions in the future, but picking my long-haul carrier is the most pressing.
Also when should I book? Best seats?, etc.
Many thanks, Geoff