There is a wide range of spot exchanges — safe and easy-to-use. Use CoinMarketCap (CMC) which ranks spot exchanges depending on their confidence indicator: https://coinmarketcap.com/rankings/exchanges/ . This service ranks and scores exchanges based on their traffic, liquidity, and trading volumes.
You can also use CoinGecko — the world’s largest independent cryptocurrency data aggregator — https://www.coingecko.com/en/exchanges. Its ranking might be slightly different from CoinMarketCap, but they both have the exchanges at the top. Keep in mind that the exchange you choose must support the withdrawal of BNB and USDT in the BNB Smart Chain network.
In addition to spot exchanges and P2P platforms, you can use online exchangers. Some users consider exchangers to be a more convenient option as they do not require identity verification. On the negative side, exchangers can charge a high commission for their services (2-3%, or even more).
Buying assets through exchangers is considered less secure compared to spot exchanges. We don't recommend using Telegram bots or other insecure ways — you can be cheated by scammers. There are also offline exchangers, but you need to find out if there are any in your city and where they are located.
Therefore, we recommend using spot exchanges as the most reliable option. However if for some reason you do not want or cannot use them, another option is online exchangers. Other ways of buying BNB and USDT are not advisable. Have a good day!