Welcome to ASF! Keep doing what you are doing by reading and learning. You can never learn to much and there is no such thing as knowing everything. Keep an open mind and soak up as much knowledge as you can
I am going to completely avoid saying you are to young etc. I am sure you have made your mind up and are going to jump in head first regardless so let`s look at it in a different way so hear me out. Why not just run the 400mg of test only as your first cycle and save the dbol for your 2nd or 3rd cycle (with test) down the road. Your first cycle is VERY important bc this is when you learn the most about your body. Are you a high estrogen converter, low estrogen converter or average? You won`t know till you run test and see. Dbol is a VERY VERY high estrogen converting compound. Not only does it have HIGH estrogen conversion but the estrogen it converts into is a methylated estrogen which is much more aggressive form of estrogen. Gyo is REAL possibility if you do not do manage things correctly. The problem is you don`t know how to manage estrogen yet (at no fault of your own) bc you have not even did a test only cycle yet.
So consider running the test only cycle. Save the dbol for your next cycle. Don`t get gyno. Eat your ass off (whole foods, high protein and high carb), train your ass off and you will grow on 400mg of test assuming your diet is on point. Don`t expect to grow without good foods and enough of them. Can`t build a house with out materials. You can have 20 professional contractors and all the saws and drills on the planet but if you do not have materials then that house is not getting built. Eat your ass off but don`t eat like a fat pig. Eat whole foods and keep processed shit to a minimum.
Do you have an AI (Aromatase inhibitor) on hand? You NEED to have one of these on hand before you ever start your cycle. Dbol LARGELY converts to estrogen and it will be out of control if you don`t have an AI. Armidex (Anastrozole) and Aromasin (Exemestane) are the two AIs you want to decide between.
I would suggest having Tamoxifen (Nolva) on hand to combat possible gyno if you was to get it in addition to the AIs
What do you have in mind for your PCT?
Let me know if I can be of any help to you. Be smart. This is a marathon and not a 100 yard sprint. Be in it for the long haul.