One of the factors that affects your credit score is the length of your credit history. As a result, it is good to have 2-3 cards that have been open for a year or two.
In addition, scoring models generally look at how much credit you have available to you verses how much credit in use. You want to have more unused credit than used credit. Ideally, you want the amount of credit being used to be 30% or less of the available credit. In other words, let’s say you have $10,000 in credit card debt. If you have 8 open credit cards, and each has a credit limit of $6,000, you are better to have a $2,000 balance on 5 of your cards, than a $5,000 balance on 2 cards.
As long as you have a couple cards with some history and use less than 30% of the available credit, you should be fine closings any additional cards that are unneeded.