Problems With The Code
If you look at the build output, you can see the compilation errors.
contador is not a valid identifier. Did you mean counter?
After this fix, you can run the code, but there will be runtime errors.
The problem here seems to be that console.readline does not return an integer, but a String. You need to parse the integral number from the string: Int32.TryParse().
Another problem was that you were trying to use the & (string concatenation) operator instead of the And (logical and) operator. I've fixed that in the code below.
Fixed Code
Module VBModule
Sub Main()
console.write ("Enter the table number (from 1 to 10): ")
dim line as string = console.readline ()
dim numbertable as integer
if Int32.TryParse(line, numbertable) then
if numbertable <= 10 then
dim counter as integer = 1
do while (counter < 11 And numbertable < 10)
console.writeline (numbertable & "X" & counter & "=" & numbertable * counter)
counter = counter + 1
loop
else
console.writeline ("The number is wrong")
end if
else
console.writeline("numbertable is invalid")
end if
End Sub
End Module
Disclaimer
I've never written a VB code before. Apologies for all the mistakes I may have made.