...Do you think it's better to save in stable coin like usdt or I should just keep the money in the bank?
It all depends on which country you live in and, accordingly, what national currency you have. If you live in America, it is better to keep your savings in USD. If you live in a country where the national currency is subject to inflation, then you should keep your savings in USDT or another stablecoin, the value of which is pegged to USD.