First, wear the bass in front of you, hanging from a strap that goes around your back and over your shoulder. If you try an play it violin style, you're bound to cause injury to yourself and possibly others.
Be careful walking around with it in cramped places places with low ceilings (seriously, lol).
I liked "Scott's Bass Lessons", among other YouTube channels.
A few lessons with a private instructor could help ensure your bass technique won't cause hand/arm/shoulder/etc. issues down the line.
Playing with others, especially if including a drummer, will help you see and, more importantly,
feel what is really supposed to be going on.
A drum machine or metronome can help with timing and certainly to an extent feel, but interacting with a real drummer is different. Interacting with the rest of the band is important too, for sure, but especially the drummer.
Maybe the biggest differences from violin will be that the bass isn't typically playing a melody and that the bass has rhythmic, kind of 'dance' (physical body movement) possibilities. There are times when it is appropriate to just to play the root note of whatever chord the guitarist is playing, maybe even just whole notes, but at other times you want to be pumping out a rhythm through varying volume of the notes played so as to match the beat, and sometimes even beyond that in a way so as to get yours and others' bodies moving. Actually, there's all different kinds of music and all different kinds of songs, so the role of the bass can vary a lot as appropriate. You could be pumping out quarter notes with a pick for chugging rock, or doing riffs, pentatonic runs, maybe on occasion a melody, I mean it goes on and on… a whole world to explore and chart your own path through. Enjoy
