great many; innumerable; plenty (indicating a large quantity)
その店にはお菓子がいくつでも並んでいる。
There are countless sweets displayed at that shop.
子どもたちはおもちゃをいくつでも欲しがる。
Children want an endless number of toys.
いくつでも選べますよ。
You can choose as many as you like.
any number; whether few or many — indicates that any quantity is acceptable
いくつでもよいから名前を挙げてください。
Please list any number of names—whatever you like.
その種類は数がいくつでも構わない。
For that type, the number doesn't matter.