Hi malika19,
Keeping track of loans is possible with QuickBooks Online and I've got just the article to help you out. It gives you simple step-by-step instructions for recording the loan and its payments so you can make sure your books are balancing correctly. Read the article below to learn how it's done.
Step 3 of the article about recording the payment also indicates how to enter the interest expense.
That should get you on your way. I'll be here if you have more questions. :)
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