Here is the AMD Link: https://www.amd.com/en/support/graphics/amd-radeon-hd/amd-radeon-hd-8000m-series/amd-radeon-hd-8850m...
But the best driver to install is your laptop's Support AMD Driver rather than AMD generic driver which is not customized for your laptop.
But if your laptop has an AMD APU (Processor with Integrated Graphics) you need to download the APU Driver which will automatically install both the integrated and discrete GPU drivers.
Also if your AMD APU is not supported by AMD and you try to install the latest HD8850M driver it will crash or not install since you need to install the last supported AMD driver for your APU.
If your laptop has an Intel APU then you can just download the HD8850M driver but the Intel Graphics and CHIPSET drivers must be the latest versions plus Windows must be fully updated via Windows Update.