Does cover of a music track have to be made using real instruments?

You could use a apple app called garage band which allows you to record and baisically creat music that's what I use for my YouTube (Nathan Copland) although iv recorded iv used the instruments on the app which are good however it would sound a lot more in time and easy to listen to if u used real instruments but if you just want to have a bit of fun recording then go for it if not and there's say one instrument available to u use it and then use other objects around the house in all of my videos on YouTube so far iv used nothing but my guitar and voice