How to write the error stream and return code from one command to variables without using a file?

Question

linux

Let's say that we have a blabla command , and two variables ERROR and KOD
The value of the exit code ($?) of our command (blabla) should always fall into the KOD variable.
If the command (blabla) worked successfully, output the result to the console (&1), in case of failure, write the stream of errors (&2) to the ERROR variable without displaying it.
How can this be done without writing to a file?

Answer 1

Something like this (I write on my knee)
RESULT='blabla 2>&1'
CODE=$?
if [ $CODE -gt 0 ]; then
ERROR=$RESULT
else
echo $RESULT
fi