I received an invoice from our supplier. We bought from them all the office equipment in the office such as computers, printer & router. They send an invoice for purchasing the equipment & service charge for the installation & other IT services.

The invoice is in detailed like as below:

HP COMPAQ - Dhs.2805
Monitor - Dhs. 690
Printer - Dhs. 1000
Router - Dhs. 320
Service Charge - Dhs. 600
--------------------------
Total - Dhs. 5460

Now, I want to enter it to peachtree program. What is the first step I should do?

Since you have an unpaid invoice, you need to be entering this through the "purchases" section of the... um, I think it's just called Payables. (I don't have it installed right now, sorry. There's the receivables, payables, general ledger, inventory, payroll... you want the payables one.)

Enter this company as a vendor, and then just enter the invoice as a purchase. The entire cost will be charged to a fixed asset account. If you don't have an account for it yet, you can add the account on the fly while you're entering the invoice.

What account you want to use is up to you. If you have Office Equipment, you can include it in with that. You can make a specific Computer Equipment account. That part is not terribly important, as long as you make it a fixed asset and put it in an account that makes sense. If you have an outside accountant who is doing your year-end work, just make sure you keep track of that cost separately and give it to the accountant so that he/she can deal with the depreciation involved.