You can manually add or change your profile picture in Planhat from your User Profile.
Click on your name in the top-right corner of Planhat, and select "Profile"
Click on the 3 dots (ellipsis) in the top-right corner, and select "Update photo"
You will be prompted to choose an image to upload. Once you've selected an image, you can crop it if desired.
Click "Save" in the bottom left (shown in the screenshot above)
You may need to refresh your window to see the change applied