Begin with songs that are simple to play. Like quarter notes at a reasonable tempo.
Listen to what bass players are doing on recordings. Not just the notes, but also the "feel," the little nuances. This may involve some ear training on your part. This is a huge part of learning to play bass, because getting even marginally good at it is a hell of a lot more than just hitting the right notes at the right time.
Play along with recordings (with the recordings' bottom end rolled off) and record everything you do. It can be as simple as playing music through a stereo system, playing your bass guitar through a small bass amp, and using a stereo handheld recorder to record the mix, i.e. the "session." Then listen to how well you did.
You will have to invest serious time for practice, that is if you want to get reasonably good by, say, the end of the year. You may have to dump other things you like to do off your schedule. Going back several decades, I can tell you exactly when I transitioned from Suck to Pretty Good. It was when I was practicing 4-5 hours a day. When I began working professionally, those hours went to 8-10 hours a day, not counting performance time.
Make sure your instrument isn't holding you back because there's something wrong with it that makes it hard to play. If you don't yet know how to do setups, take it to someone who does. Just be careful on that point, because there are plenty of butchers out there whose work can cause long term damage, some with tens of thousands of Youtube subs.
Find a tone you like, and watch that person's technique, especially his/her right hand position. Some people play close to the neck, some close to the bridge, some somewhere in between. The advanced players can adjust that position on the fly to fit particular songs or specific parts of a song, but you can save that for later.
Don't bang the strings. Keep your fingers' first joints flexible and gently come across the tops of the strings. There are lots of players out there whose plucking fingers look like they're trying to pick at a scab or a callus. That's not the path to a good tone.
Metronome. But one and spend time with it. Boring? You bet. But it pays off.
I could keep going but I'll quit here.