If you wish to use sf symbols in the macOS, (including the colored version) You need to install macOS 11 beta or later, then it works as usual, otherwise you have to export a template and import it to the assets catalog, then you can use it as a normal image. So:
if #available(OSX 11.0, *) {
Image(systemName: "trash.fill")
} else {
Image("trash.fill") // Imported as a supporting format like PDF (not SVG)
}
Another way is to use the symbol directly in the text:
Text("") // The symbol itself can not be shown on the mark down of the StackOverflow

Remember that you should embed the font in your application or the destination should have the SF Symbols App installed