A USDT wallet is any wallet that supports USDT on the network being used, because USDT runs on several networks, among them TRC20 on TRON, ERC20 on Ethereum and BEP20 on BNB Smart Chain. A balance on one network does not move to another by itself. To create a USDT wallet, set up the app as usual, back up the words, then add USDT and choose the network before copying the address. Fees are paid in that network's coin: TRX on TRON, through energy and bandwidth or TRX burnt for them, ETH gas on Ethereum, BNB on BNB Smart Chain.
Creating a bitcoin wallet takes a few minutes in most apps. The app generates fresh keys, shows a short list of backup words to copy onto paper, and then displays a receiving address. How to create a bitcoin wallet safely comes down to that backup step, because without it a broken phone takes the coins with it. A bitcoin account is something else: a login at an exchange that holds keys for its customers. Anyone who wants to open a bitcoin account there usually faces identity checks, while owning bitcoin in a personal wallet needs no account at all.
How to choose a bitcoin wallet depends on its intended use, not on a ranking. A few tests help. The keys stay with the user, or it is clear who holds them. The backup words follow a common standard that other compatible wallets can restore. The sender can set the network fee, which matters more than any promise of a bitcoin wallet with low fees, since that fee goes to the network rather than the wallet. Open source code or a long public record counts for more than lists of the best wallets, which are often paid placements.