Download and install Phantom from the following link: https://phantom.com/
Buy or send SOLANA to your wallet, you can buy it directly from Phantom or from one of a known CEX
Go to https://raydium.io/swap/ and connect your wallet, then add the $NDAS token using this contract address: yCYSJATPJiFgtE1Up7LFGQEV8XLZ5Ma7Y53JnXKpump
After adding the contract, you should be able to swap SOL for $$NDAS. Give some time for the transaction to be confirmed.