Open the sheet you want to add the render to.

Select the "Add Image from Various Sources" tool in your toolbar and the modal will open up where you can select the "Upload image from Computer" option.

Your computer's storage will open up, where you can select the particular file and it will be added to your sheet.

Place it in the sheet as required.

Select the image and the properties like size, transparency, orientation will appear in your design panel on the left side. You can make any changes you want there.