You can use Binance to buy/ Sell cryptocurrency. Make an account on Binance and do a KYC to activate your account. There is a section called P2P, where you can sell/ buy USDT or Bitcoin in your local currency. After purchasing BTC or any other coin, do not store it on Binance Exchange, transfer those tokens ASAP to Metamask or Trust Wallet (You can use other wallets as well).
First, when you want to buy a small amount of bitcoin, it's not advisable to use an exchange account. Aside from the privacy, the withdrawal fee that you will be charged might be close to what you purchased on that exchange and want to move out of.
Currently, the bitcoin withdrawal fee on Binance is close to $13 worth of bitcoin, which is very high compared to what you will be charged if you buy from Dex, and you can move that directly to your personal wallet.
Another thing is that TrustWallet is a close-source wallet and it's not recommended for use; Metamask is good for Altcoin; and UnstoppableWallet can also go for altcoins. If you want to recommend the best wallet for bitcoin holding, you should recommend wallets like BlueWallet and Electrum; they are some of the best open-source wallets here, among many others.