Don’t get overwhelmed thinking you have to learn everything immediately, it doesn’t work like that, take your time, solidify playing simple tunes. Repetition on the violin is more effective than on any other string instrument, but make sure you do it correctly. Scales help you to play in tune, they also help when it comes to playing keys with lots of flats. Arpeggios are great for learning to play in tune, you can also slide the arpeggio up the neck to practice shifting, arpeggios are found in lots of classical pieces, If you don’t know what scales sound like listen to them on the internet so you have an idea of the intervals between notes. Scales have to be played perfectly in tune and are the basis of all music, but especially violin, on a guitar they are easy, but not so much on violin as you have to use your ears, have a glance at maestronet.