If you are very new to golf it is wise to get a reasonably priced putter at first, as your first putter will always act as a stepping stone to a better second one, and a better third one. Things like the “feel”, the sound, and the alignment aid on the club can be a lot to consider if you haven't at least owned a putter before.
Players get the most out of their putters by hitting the ball out of the centre part of their club face. This is something that develops over time, along with your posture and use of any alignment aid that may feature on your putter when you stare down on it.
The good news is, putters are exempt from the sizing restrictions of other clubs, which means they come in all shapes and sizes, often matching you instead of you having to match the club. Cheaper putters still perform very well overall, but more expensive ones include top quality materials that provide a better 'feel' and roll. We would advise you commit to one putter, one putting style and one ball, all at the same time to ensure all three combined help you form good habits.