Hi guys.
I need some help. My bikes chain isn't well aligned, it has a coaster bracke hub and I don't really know if there is any way I could fix this, is there spacers for coaster hubs? The problem is that I've bought a new chain and it doesn't fit, impossible to ride. The old one I was using was thinner and for some reason that made it work kinda well.
Thanks, hope you have some advice for me.

Did you get the right chain?

u can use a bottom bracket lockring as a spacer.

Yeah 1 speed chain, fits fine on chain ring and cog but when I put it on both the bike and spin the chainring because of the angle the chain doesn't fit properly on the chainring

Your "Chainline" is wonky.

You need to take two separate measurements for us to properly help you.

1. How far is your front chain ring from the center line of the bike?
2. How far is your rear sprocket from the center line of the bike?

Measure right to the tip of a tooth.

Once we know these numbers we can help you figure out the best way to make adjustments.

Which brand and and model coaster brake do you have?

You can read here to see the best/easiest way to measure your chainline.

All About Bicycle Chainline