Nerdwallet[1] is an excellent resource for comparing credit card options.
My recommendation would be to get only no-annual-fee cards, and to get one with purchase protection benefits and one with high cash-back. The former would be for purchases of products that might benefit from extended warranties, return protection (covers you when vendors don’t have a good return policy) and purchase protection (if you break your new toy in the first 90-120 days). American Express has a number of no-annual-fee cards that carry these benefits.
The other card would be for purchases that don’t benefit from these perks: groceries, cable bill, medical copays. Here the best perk is getting cash back on your purchases.
Good luck!