How to buy an amplifier?

Excuse me, could you possibly provide some guidance on the process of purchasing an amplifier? I'm somewhat new to this and I'm not entirely sure where to start. What are some of the key factors I should consider when selecting an amplifier? Is there a specific brand or model that you would recommend for a beginner like myself? Additionally, what's the best way to ensure that I'm getting a good deal on the amplifier I choose? Thank you for your time and assistance.