For the past five years or so, I've taken singing lessons. I really recommend it to anyone who has even the faintest interest, even if you feel like you can't carry a tune in a bucket. What I learned the first four to six lessons was enough to make a substantial difference both in my vocal quality and in my comfort in singing for long periods (one of the first things you learn, essentially, is how not to shred your vocal cords). One thing I love about singing is that it's one of the most democratic arts. You don't have to buy or maintain instruments -- you were born with it. Almost everybody is capable at least of some degree of singing. There's no gadgets to buy to improve it. And no matter what kind of music you like, there is a place for vocals. You can sing by yourself in the shower or in front of a band or in a chorus or in a congregation, if that's your thing.
Aside from the benefits of being able to produce aesthetically pleasant sounds and the fundamental pleasures of mastery of a skill, I recommend it to anybody who wants to become more aware of and comfortable with their body and/or with expressing their emotions.
I'm sure that there are good free online lessons for singing, and I've used a lot of videos for practice, but I really encourage seeking out a teacher if you can. Covid has been bad for their business, and there's no replacement for face-to-face instruction. (The good news is that, unlike something like the piano, it's absolutely feasible to get useful instruction over a video call!)