Often bass players "pick" the bass strings with two or three fingers instead of using a bass pick, whether for walking bass lines, bass triads, outlining bass chords, bass blues licks, bass arpeggio runs, ocataves, etc. There are many ways to implement the bass fingerstyle technique but remember we are simply talking about the use of our fingers to play the strings on a bass as opposed to using a pick.

The key question you may ask is what should I do? Use a pick or use my fingers. If you are thinking that way it might be better for you to redirect that idea to the new idea that playing with a pick or playing with my fingers gives me different tones even though I may be playing the same thing, but it also may be more practical in some styles or situations to use one method or the other. You don't need to limit yourself in your playing. Even with fingerstyle playing, there are different techniques and ways to play with the fingers. And with a pick, there are different picking methods.

Some bass players prefer not to use a pick at all. Others prefer using a pick.

Why not learn and experiment with a number of methods so you can play a greater range of styles and determine for yourself what you most prefer as you main method of playing.

The most important thing though is not to get caught up in this, and forget that the real big task for you is to actually learn the knowledge of music, how to apply it on your bass, and how to master the bass neck with whatever playing method you use.