If you are looking for something that is probably not a scam, there is a UN citizen platform for carbon offsets. [0] FWIW the platform is supported by a number of major corporations including Microsoft. [1]

[0] https://unfccc.int/climate-action/climate-neutral-now/i-am-a... [1] https://unfccc.int/climate-action/climate-neutral-now/i-am-a...