Can I mint 1 NFT few time(20 times) on Solana candy machine v2?
Solution 1:
Yes. You could mint them all as NFTs with the metaplex source code.
Using the candymachine V2 is one way: https://docs.metaplex.com/
When "preparing the assets" in this step: https://docs.metaplex.com/candy-machine-v2/preparing-assets I would just set 0-10.png to be all the same image and with whatever metadata you want.
Note: a technical aspect of this to remember is that these will be minted as NFTs so even though they have the same image they have a different mint hash. If this doesn't matter than this is a perfectly fine method to use.