20 is a little young but if you insist i copied a sticky posted by Tee for you to read
First cycle advice:
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I always get people asking, “What is a good first cycle?” My answer is, and always will be, “TEST!” There are many reasons why test is recommended for a first cycle, but here is a few quick answers for you.
Taking any steroids will shut your natural testosterone production down. This can lead to impotence. Deca and tren are not the only steroids that can cause this; any drug can, when not accompanied by test.Therefore, test should be the base for all cycles, and you should know what it will and can do to you. You need to know if it raises your blood pressure, if you are prone to gyno, if you will retain water or not, and what gains it gives you in the dose you are taking. Adding another drug in the first cycle stack can cause problems.
For example: You take a first cycle of 600mg test and 400 mg Deca for 12 weeks. All of a sudden, you start to get gyno symptoms. What is causing it? Is it the test or is it the Deca? Well, you better know because you will have to know what to take to address the problem correctly. Had you taken a first cycle of test only, you would know if you are going to get itchy nips from it or not.
I hope this explains my position on why I recommend test for a first cycle. You will have plenty of time in the future to add in all kinds of other AAS if you wish. Taking one step at a time will definitely help you to understand your own body better than just jumping in with both feet and getting into trouble.
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All advice given is strictly for entertainment purposes.
hope this helps !