How to get rsk for gas fee
Hi! There is no “rsk” coin. What you need to pay for gas is rBTC, and to get rBTC you can use one of the many bridges or centralizes exchanges that trade BTC por rBTC.
If you want to use the native bridge, then you can do so programmatically or you can use one of the existent front ends, such as https://app.2wp.rootstock.io/