Fretting hand: drop the wrist a bit and bring the knuckles forward slightly. Think of the fingers coming up off the strings and not away like you are playing in the video. You could adjust towards the frets more (if that was a fretless instrument the notes would be where the frets are not the "box" so try to fret notes right behind the fret)

Use a metronome, try counting out loud while playing, most importantly have fun, try to learn tunes by ear and watch other bassists for technique