I would suggest a private taxi, purchased with your credit card, in the terminal. You can get your bearings later after in the City. Even if you end up spending an extra US$10 or $20 from less expensive alternatives, it is best for the first time visitor. I can't give updated info on UBER and where a pick up / drop off might be (generally not convenient) as the new terminal just opened, and I'm not familiar with the set-up.

You can use a CC for most things, but keep some CL$ pesos on hand - you'll need it for taxis (typically cheap and reliable during the day, but be careful at night - not for safety but for taxistas trying to rip you off) and for small incidentals. That said, even some of the street performers now accept a Square equivalent. (Pretty funny when you're eating outside, hear a song, and then she comes around, people say they don't have any $, and she takes the card reader out.) Note that most ATMs have a huge CL$ surcharge for foreign cards, so find one that doesn't, use a card from home that rebates your fee, or take out everything you think you'll need at once.