When you are a solo creator, it's harder for you to get your work out there. Most larger game developers have people to promote their game ( eg the voice actors of the game, writers etc) and they can afford to run ads. However, smaller creators don't have this. You can help these struggling creators. Like Indie game devs don't have a large crew like a company like Nintendo.
If you cannot afford to buy their art or whatever, you can merely share their work on your social media. If you're a YouTuber, you can mention your friend's work in your videos. It's very crucial to link back someone's work when you use it. Review the game or whatever and link to where people can find it
Merely using their work and linking it can drive the sales.
A few weeks ago a YouTuber called Mat Pat didn't link a game he played and the game's devs called him out. When he justified not linking games then the Undertale creator came in. I agreed with the Undertale creator and the Heartbound creators. Smaller developers have trouble getting their work out there like myself. They depend on people buying their work. Someone people aren't so lucky and can't get a 'real job.'
Even though you can't afford to buy their work, you can still share it on your socials. If you can afford it, make a review on the whatever and link it to help them get supporters.
edit; I did not word my phrase right when I said if you can't afford someone's work you can still use it. I was referring to art. Say you want to repost, link the original source like Deviantart. And if the artist has their store on their site people can go in and buy their art if they like it. You're just showing an example of the person's work. Most of the time games will have free demos. If it's an episodic game, the first episode will be free and the rest is paid. You can use the demo or free episode to promote the game ( say you can't afford the full game) and link the full game where people can buy it. Sometimes most devs will give you a free key in exchange for reviewing the game etc.
Thought I reword this because someone thought I was condoning piracy. I am not good a verbal expressing, this got me bullied out of a Facebook group.