how to import uddf file to the garmin descent g1 or any way could comvert the uddf logs to garmin supported files?
You'll probably need a 3rd party solution. Principally, Garmin Connect and Garmin Dive are designed for keeping data from Garmin devices, not as an universal diving app. You can have a look at nradov's Suunto log import script - perhaps it could be modified to work with UDDF too: https://github.com/nradov/SdeToFit