// This creates the Embed builder
var eb = new EmbedBuilder();
    eb.AddField("RandomField", "Hello, my name is random Field"); 

// Here you make an array with 1 entry, which is the embed ( from EmbedBuilder.Build() )
Embed[] embedArray = new Embed[] { eb.Build() };

// Now you pass it into the method like this: 'embeds: embedArray'
await DCW.SendFileAsync(filePath: "C:\RandomFile.txt", text: "Embed", embeds: embedArray);