ideally, you would start with an injectable test for your first cycle. its safer than orals and the gains are better. 10 to 12 wks of test cyp at 300 to 500mg EW along with an AI and PCT. orals are toxic on the liver, effect your ldl/hdl and can lower your appetite. because of this, guys mostly use them as a tool to add some water mass and strength quickly at the begining of a longer cycle, while they wait for the test to kick in. 10 wks gives you enough time to really make a decent impact on your physique. because of the toxic nature of orals, 10 wks is too long. for most orals, 4-6 wks is common. also, while using test, you can get away with using far lower doses of an oral to evoke a great response, than if you run that same oral alone...at least IME.
if you insist on using an oral to start out, look in to anavar around 50mg ED for 6-8 wks. the side effects are low. strength is great and the gains are solid. you wont get huge running orals like this, but you can gain a few lbs. make sure you put together a good PCT for 3 wks following the use of any AAS. i would personally suggest the GP anavar that naps carries. i have had good expreiences with it while dieting. its a top quality product. because anavar is expensive, it is often underdosed or faked. GP is the real deal. go to a good message board like juiced muscle to reseach exactly what PCT is all about. there is a ton of good info there. far more than i can share with you in a single response