You didn't give us much info to go with, so I'll do a general response.
You first need to install intel gpu drivers, then amd gpu drivers. Once you do that you should have either "AMD Radeon settings" or "Configure switchable graphics" (not sure if the second one is 100% correct) when you right click on your desktop. Both might take a while to open, so be patient.
Case 1: AMD Radeon settings
1. click on the AMD Radeon settings
2. click "preferences" on the bottom
3. click "Radeon additional settings"
4. follow case 2 steps
Case 2: Configure switchable graphics
0. on the left there might be an option named "switchable graphics global settings".
If there is, click it and set the default for all apps. Maximize performance is the...