Although it's recommended to use RV toilet paper in your RV toilet you can safely use regular toilet paper or septic safe toilet paper in your RV.
Most toilet papers you buy in the store are now septic safe and break down pretty quickly in the RV toilet.
There's really no need to buy special RV toilet paper for your RV toilet as it's just more expensive than regular toilet paper that does just as good at breaking down in the RV toilet tank.
Just be sure to not use too much of the toilet paper in the RV toilet and add the RV toilet chemicals when needed and you'll be just fine.
I have an RV I use sometimes and I just use my regular toilet paper and it never has been a problem for me or my RV.
Also just be sure to empty the RV toilet holding tank when it gets near full and you'll be just fine.
When emptying RV wastewater tanks it's best to empty the toilet or black water tank first and then use the grey water tank to flush the sewer line after that.