use suzuki genuine oil or any other good oil preferably 10w-40 and change after 5000km
gear oil at 40,000 and brake oil at 80,000
consult your manual for maintainance chart or go to suzuki 3s at 40k,60k, 80k(every 20k) kms get a service estimate all the required stuff will be written on it,so that you can get the work done from them or any other place
right now if you don't have previous service history you are looking at servicing throttle body,spark plugs,air filter and oil change alng with brake service