If you want to use a sample of someone else's music you need the permission of the song's copyright holder (the writer(s) and/or the publisher), and permission from the owner of the recording, usually the label.
Please remember this also applies to samples taken from movies or TV shows.
Without approval from the copyright holders, you may NOT upload the music.
Where to find royalty free samples:
With over 64,000 royalty-free music samples, SampleRadar is a digital library of sample packs for music producers. Listed alphabetically and categorized into themes, SampleRadar guarantees their samples are 100% royalty-free, meaning DIY artists can use the samples in their tracks completely without risk.