You need good sounds to make a good beat. Sound selection, simply put, are the sounds that you choose to make your music.
Whatever sounds you choose are up to you, you should consider your genre, style etc.
We suggest that you not only take your time picking sounds when making a beat. We suggest you take your time when searching for, and downloading drum kits, sound presets, samples, and other types of sounds online.
There’s plenty of free drumkits, sound presets, and samples you can download online. Just search for example “Free Drum Kits” on YouTube or Google.
If you’re just starting off, download some free kits. Once you find your niche sound (rnb, hip hop, trap, trap soul, edm, etc..), you should then download or purchase more specific kits to cater to your sound.
There are other sounds you can search for and download such as sample loops, effects like a bird chirping, or someone laughing; this can also include VST presets (sound presets for your VST, Electra X for example).
The VST’s on your DAW come with presets, however you can download or purchase more for enhanced quality / selection, these are known as sound banks or sound presets.
Also note that certain sounds are simply popular right now, therefore using new, popular kits, can put you at an advantage. Again however, the creativity of beat making and the sounds you choose, are totally up to you.