Which is better for a beginner uhf or vhf?
This is a loaded question without you providing some more clues as to just what your looking for.
A few comments on the bands. First of all, the lower in frequency you use, the further the range will be for normal communications. In other words, the VHF band will allow a greater range than the same kind of setup on the UHF band. In using 6 meters, you can get even further communications range than at a VHF frequency.
With that said, there are a number of issues to consider in what your trying to do. At VHF, on the 2 meter band, generally there are more repeaters available than what you will find on the UHF ham band.
If your talking public safety and commercial radio operation, the use is about split evenly between the two bands.
Antennas at the UHF band are smaller in size than a VHF band antenna. But your coax cable losses are greater at the UHF band than they are at the VHF band. You can get more gain in a UHF antenna than you can in a VHF antenna of the same size.
You will probably have more external interference on the VHF band than you will at the UHF band. Things like cable TV leakage, radiation from devices like TV sets, computers, computer network devices like hubs, switches, routers and network interface cards (NIC) all generate some noise that can fall in the VHF band and on lower frequencies.
I know this doesn't directly answer your question, but you didn't give much for us to go on in your wording of your question.