Before you start doing your own presale it's super important that you do understand what your contract can do.
Ropsten Test Network
For most cases the Ropsten Test Network is the best choice, it has a running swap on V2 Uniswap and everything you need. For testing your Contract on the Testnet there are many guides and Videos on the Internet, we also made on for you:
Ropsten Ethereum you can get for example from here:
Ropsten Ethereum (rETH) Faucet
GitHub - ConsenSys/ethereum-developer-tools-list: A guide to available tools and platforms for developing on Ethereum.