A brokerage account allows you to buy stocks and other securities (such as ETFs, options, mutual funds, bonds and more). You can open an account with an online brokerage, a full-service brokerage (a more expensive choice) or a trading app such as Robinhood or Webull. Any of these choices will allow you to buy stock in publicly traded companies.
However, your bank account or other financial accounts will not allow you to purchase stocks. But your bank may operate a brokerage, so you can open an account with the brokerage and buy stock there. For example, Bank of America owns Merrill Edge, J.P. Morgan Chase offers J.P. Morgan Self-Direct Investing and Wells Fargo operates WellsTrade.