Hello, @moheman aldulimy 

You can refer this thread also:  https://www.outsystems.com/forums/discussion/86671/how-to-generate-random-alphanumeric-numbers-and-store-then-in-database/#Post366438 

you want to generate a random string of length of your choice in JavaScript. In that case, you can add a JavaScript node with the following code and and an input parameter TextLengthnof type integer and an output parameter of type text called Uid to it. 

function getRandomString(length) { 

 var s = '';  

do { s += Math.random().toString(36).substr(2); } while (s.length < length);  

s = s.substr(0, length);    

return s;

}

$parameters.Uid = getRandomString($parameters.TextLength);

hope, this will helps you.

Thanks & Regards

-- Priya Jhode