Yes, you can pay a vendor by tranferring funds directly from your QuickBooks Checking account. However, once the payment is sent, you'll need to reach an internal agreement with the vendor to confirm receipt of the fund, Nika.
To transfer funds from your QuickBooks Checking account, follows the outlined steps below:
- Select Transfer then select Transfer money.
- Enter the amount you want to transfer.
- In the From dropdown, select your connected bank account.
- In the To dropdown, select your QuickBooks Checking account.
- Select Next.
- Select Finish transfer.
After confirmation that money has been received, you'll have to manually mark the bill as paid in QuickBooks Online (QBO) to update records. You can click the + New icon and then select Pay bills. I've added screenshot for reference:

On the other hand, you can also pay another person or vendor directly from your QuickBooks Checking account using QuickBooks Bill Pay.
On top of that, to give you more information about QuickBooks Checking, read this article: Checking FAQ.
Let me know if you have any other payment or transfer concerns. I'm always right here to help you as always.