And even after a couple of years you can certainly be having fun with it! I started playing bass in 1965 and played my first gig - a battle of the bands - in 1966. We knew 5-songs and played 3 of them. My girlfriend and I went to the movies every Saturday for 2-years as payment for partaking in that gig! Yeah, it was high school. Get to know all the notes in the Money frets first (first 5) then the next 7 frets and everything from fret 12 on up is a repeat of notes you already know.It takes a couple years to learn the basics, about five years to get pretty good, and about 10 years to become an expert. So if you’ve got 10 years, it can be done.
Learn your arpeggios (root, 3rd, 5th, and octave for each chord guitars and keys play) because those are the notes you have available to use as a bassline behind the chords. You can spell out the chords by playing the chord tones on your bass. You can get by with Major and minor arpeggios at first, but you will want to also incorporate the minor 7th for the 7th chords like G7, the major 7th for any maj7 chords and the 9th, which is a whole step above the octave. All of those 7, maj7, 6, 9, chords etc. just supply additional notes you can use if you want to. You don't have to use all of them and just the major and minor arpeggios will get you started. But you need to learn and know your arpeggios.
Play along with songs you like and learn the bass parts. With a little knowledge about arpeggios you'll start to recognize what the bass players are doing. If you are practicing alongside a song and are stopping anytime you make a mistake, before you stop for the day, be sure to play it all the way through mistakes and all. Don't stop for mistakes. When you perform live, you are going to make mistakes from time to time and the band is NOT going to stop for you to try to do it over to get it right. So you'll need to learn how to recover from a mistake and carry on with a smile on your face so no one but you knows you screwed up. It is show-biz after all.