can I use my road bike off road? I have several bikes. I noticed that 90% of times I go on road  so I got myself a road bike. But, can I use it for off road? Nothing extreme maybe some dirt roads or with small stones or poorly maintained roads. There is a really small amount of rains here so mud it is not a danger. The idea is that I can lend it to a friend to make some soft off road routes or use it myself and lend a more off road bike.
There's a whole sport - cyclocross - that involves riding road bikes off road. Typically the gearing is a little lower than a stock road bike, and these days a lot of them have disk brakes. Most will take fairly wide tyres, 38mm is not out of the question.

For riding a stock road bike off road, I'd look mostly at tyres. If you can find some that will clear your frame that have a bit of tread that will help a lot. Puncture resistance may also be worth while, you're more likely to find thorns off road. I would also experiment with lower tyre pressures, as that may improve traction.

Other than that, I'd just ride and see what happens.