No, you can't get it for free, either you have to buy it or someone has to gift it to you (the minimum being 4$)
So instead of you paying here are some ways to have someone gift it to you!
1)You can either enter some giveaways where winner gets a month of supporter, there are also giveaways where people just give a month of supporter to the 10 first people to ask for it or something along those lines.
1)You could also ask for it, shoot your shot ya know?
3)The longer method thought would be to have a friend gift it to you for your birthday, or just meeting nice people online who are willing to give it to you.
Speaking from expercience here for the third tip, I once just said in a discord server (osu!alternative) the following: "Oh man I ran out of supporter I'm gonna buy another year of it this week"".
That same day someone (I still don't know who lmao) gifted me a month of it.
Just goes to show that there are ways to get it for "free" without spending any money yourself.