Kinda gonna reinforce the thing about structure. Forget orchestrating anything until at the very least you have a solid A and B section (verse/chorus.) Right now you only have an A section. Remove all other instruments except piano or guitar (whichever you’re composing on) and then come up with a B section. You can then at least alternate between the two sections experimenting with different orchestrations on each repeat such as an entire A section with pizz. strings and woodwinds playing the melody for example.