Cardano is a public blockchain platform. It is open-source and decentralized, with consensus achieved using proof of stake. It can facilitate peer-to-peer transactions with its internal cryptocurrency, ADA.

To be able to buy token in the public blockchain you need to own ADA. Every transaction in the blockchain use ADA as fee, and cost normally 1-2 ADA to send or receive. Every trading platform in the network (DEX) is priced to just ADA.

How to buy ADA? I recommend the biggest exchanges to begin with or You have to register yourself there, email, credit card etc and even do a KYC where you identifies yourself with passport/ID and also connect bank account to be able to send back. You could buy ADA from your credit card, and they will arrive in your wallet on your account. Its totally ok to just hold your ADA at coinbase/Binance, but most holders send the ADA to a personal wallet. You couldn’t use Cardanos full potential if you store on these exchanges, and of course we would control our own assets in our own wallet.

There are several wallet to use but I recommend CCvaullt or Nami Both these wallets have access to browser extension which is a requirement for trading on DEX and NFT (smart contract)
When your create your wallet it will manage a seed phrase of 15 or 24 words. Write the phrase on paper and hide it, this seed could open your wallet any time and on any wallet you wish. Secure it. You even have to create a spend password which validates your transactions, don’t save on computer, and use long password. (edited)

When you have created your wallet it would show 0 ADA, and there is often a receive or send button. If you like to send just copy address and put in square. If you want to receive you just generate an address which begins with “addr1” and send away your ADA or token/NFT. To be able to buy on DEXES or trade NFT with smart contracts you need to lock 5 ADA in something called Collateral. its quite easy in both Ccvault or Nami (go to preferences or settings). Its a good advice to allways have at least 10 ada in wallet.
If you buy 100 ADA on coinbase, just enter the wallet on account aon ADA and mange send, go to receive on CCvault or Nami and copy address and put in coinbase (coinbase have security to send, password or authenticator) and the ADA will be stored in wallet.

If you have done everything i mention here, just visit muesliswap or Mineswap, Sundeaswap and start trading. You need to connect your Nami or CCvault to these web sites (its easy)