Arc Testnet's native gas token is USDC itself, so a single faucet request covers both gas and app funds. Circle runs the actual faucet, public, free, no account needed, we just point you at it.
0x169737f2f93856fa72674b4771d59cb7b1979c8cCopy the address above, click through, paste it into the “Send to” field. Arc Testnet is already selected by default there. Rate-limited by Circle, one request per address every 2 hours.