I need summary for my 1 supplier's all transactions in QB (it includes bills and payments), is is possible to get. If yes, how?

Let me help you run a summary for all transactions you have with your supplier, @docssolutionize. 

You'll want to run a Transaction List by Vendor Report to view the bills and payments you had with this one supplier. Here's how to do it:

1. Select Reports on the left side menu.
2. On the search bar, type Transaction List by Vendor Report.
3. Make sure to Switch to classic view, then click Customize.
4. Click the filter drop-down and then tick the Transaction Type checkbox.
5. From the drop-down beside Transaction Type, select Payments and Bill.
6. After this, select the Vendor checkbox. 
7. Click the dropdown button beside it and choose the specific vendor.
8. Select Run Report once done.

I've also included some screenshots below for visual reference:

When generating the same reports in the future, you can refer to this article to save time: Memorize reports in QuickBooks Online.

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