Yes, you can buy cards with Starbits. Just go to collection and click on the card you want to buy, then 2 parts will appear (Cards and Market). In the Cards section, it shows the number of cards of that type you have and the option to sell them. In the Market part you will see the offers of those cards at the moment for you to buy, they usually sell for Starbits, Swap.Hive and Starpro but it depends on who is selling the card.

Before there was a way to get cards when you reached a certain number of missions completed, you got 1 pack and in it you got 3 cards but this function was removed and you are only able to have cards by buying in the market or buying packs.

The game currently is basically just clicking and waiting for the mission to be completed, the more Fans you have the more Starbits you will earn, currently I have 20,000 fans and I manage to earn an average of 10,000 Starbits daily but I don't spend all my time in the game. There are missions that allow you to earn cards in the game but you have to pay to complete them, they are the seasonal missions that appear (there are none at the moment), they cost Starbits or you need to be lucky enough to get a certain card in the packs to complete the mission and win more cards. There are also Fan Club missions that cost Starpro to do and give you Fan Club cards.

If you have more questions, you can ask me, I don't know if I can answer everything you asked and I think I said a lot lol.

!PIZZA
!PGM