You should get a 1099 DIV or 1099 INT or 1099B for investments. You might get a consolidated 1099 from a fund or broker. It will have sections for each kind of 1099 to enter in the right place. You do not report any dividends or interest or transactions in a IRA or 401k account.
If you have the dividends reinvested in the stock or fund you still have to report it. And be sure to add the dividend to the stock/fund cost basis when you sell because it bought more shares.
