WHERE DO I ADD THE TOTAL INTEREST INCOME EARNED FROM SEVERAL BANKS AND CAN I ADD ALL OF THE INCOMES INTO A TOTAL AND ADD TO THE RETURN.

Yes, you can enter your interest income in TurboTax Online. Here's how to do it:

 

1. Sign in to TurboTax. 
2. Select Income & Expenses.
3. Select Pick up where I left off or Start.
4. Select Start or Update to the right of Investments and Savings (1099-B, 1099-INT, 1099-DIV, 1099-K, Crypto).
5. Answer the first question Yes, or if you already have some income here, select Add investment.
6. Select Enter a different way. 
7. Select the Interest tile and Continue. 
8. Select Type it in myself at the bottom.
9. Enter the bank's name.
10. Enter your income in box 1 or 3 as it is on the 1099-INT.
11. If you have other boxes filled in on your 1099-INT, check the box next to My form has info in other boxes (this is uncommon).
12. Complete the rest of the form, then Continue.
13. Answer the remaining questions based on your situation. 
     

As far as adding up all of your interest and just making one entry, it is best to report the interest from each bank separately, because you need to report the EIN of each bank in order to e-file your return. 

wage and income section; then interest and dividends. if you did not get a 1099-INT pretend that you did. The additional payer and recipient's information can be omitted as well as any lines/boxes with zero or blank.  you can use 1 1099-INT per bank, different banks require their own 1099-INT