This guide will let you know how to make a wheelbarrow with gold.
The first thing you need to do is to dig one block of the ground and add an armor stand in it. Place a golden helmet at the top of this armor stand.
Then add a composter at the top of the helmet and two piston on this composter. And then place a white concrete block on the top and four on the right side as shown in the image below. Use a redstone block to push the pistons down.
It brings the armor stand in the composter. The next thing you will need to do is to fill this composter with carrots and add a spruce fence gate in front. Add a grindstone at the back as shown in the following image.
You have successfully made a wheelbarrow with gold.