@hosseinimr93 Thanks for good reply 
I appreciate if you could also reply these questions
A) I would like to do some Bitcoin demo trades on Kraken before I do live trades. As I see, Kraken does not offer demo account. What is the best way for me to do?
B) Is there an online fee calculator? I would like to have a better understanding for the fees with the leverage.
Let me answer these questions with direct links:I appreciate if you could also reply these questions
A) I would like to do some Bitcoin demo trades on Kraken before I do live trades. As I see, Kraken does not offer demo account. What is the best way for me to do?
B) Is there an online fee calculator? I would like to have a better understanding for the fees with the leverage.
AFAIK, there is trading bots which can calculate the exact rollover fee, trading fee before opening the trade.
A) https://support.kraken.com/hc/en-us/articles/360026192132-Test-demo-accounts
B) https://support.kraken.com/hc/en-us/articles/201893638-How-trading-fees-work-on-Kraken