You can not clone bitcoin because there is nothing there to copy, bitcoin are result of caculation on the blockchain data, to clone bitcoin you have to alter the blockchain data, and blockchain is designed in such a way that since data is stored and secured they can not be altered this is common misconception.
It cant be clone but it can be forked or created something almost the same with bitcoin. Many users or developers have tried to recreate bitcoin with a different name but has the same purpose but since bitcoin is the first its literally hard to clone.
Yes mate speaking of Bitcoin Fork, Bitcoin has been hard forked numerous times, we have seen some results of Bitcoin folk Bitcoin cash, Bitcoin SV, Bitcoin gold this are the popular ones but they all did not come close to being like Bitcoin. The real deal to the OP's topic is that Bitcoin can not be cloned, imitated.