Can I use categorical and numerical data variable at the same time in randomForest in r?
In general you can always transform categorical data into numeric data. Many experienced STATA users need to do routinely. If you have gender variable coded as "male/female" you need one binary gendervvariable recorded as 0/1. If you have four levels variable such as main role in a football team "goalkeeper/defense/midfield/attack"  you could take midfield as reference and generate the goalkeeper, midfield and attack variables all coded as 0/1.
In caret, the dummyVars function allow to create easily dummy variables. 
Here an example with cylinders transformed as factors and then dummyfied:

 library(caret) 
 mtcars$cyl &lt;- as.factor(mtcars$cyl)
 dmy&lt;- dummyVars(" ~ .", data = mtcars, fullRank=T)
 dummy.mtcars &lt;- data.frame(predict(dmy, newdata = mtcars))
 head(dummy.mtcars)