Why lose weught before you enhance????

So I asked this question in another post but I guess they didn't post it, so here it goes again. I' a 45 year old ex-athlete you could still dunk at age 36. I was healthy and strong until 2014 when I was life flighted out if the blue due to a ten inch blood clot in my heart and a six inch clot in my lungs. survived 4 open heart surgeries, but lost my thumb and part of my finger. It's taken until now to start lifting again. When I got out of the hospital this last time I was diagnosed with low-t. levels were 390ish range. The hrt pellets and program are very expensive , can't afford that right now, so I friend of mind hooked me up with some test cyp and also gave me a bottle of 100 10mg Anavar. I know Mr. Usa 1987 and he told my I should just try to put on as much weight as possible, so when I do cut I would have something to show in his words. So I have been on 500mg of test cyp per week. This week will be my 3rd week. I missed a shot last friday and took it tuesday because I was told wouldn't hurt because it was still in my blood. Joined here the other day and everybody said that I should have dropped down from 30% body fat to 15% first. Why is that. I was told different. Also want to know if it would be better to do a longer cycle of anavar ie. 20, 30 or 40 mg cycle or a shorter cycle of like 50 or 60 mgs ?? Please educate me fellows and ladies. the test is working I feel better obviously, so I don't know what to do. Expert advice with my specific situation in mind is what I need. Thanks in advance!!!