Generally people pct for 4 weeks so the 20/20/10/10
Would be the dosage every day for the respective week ie 20mg nolva every day for the first and second weeks, 10mg nolva every day for the third and fourth weeks.
Nolva is short for nolvadex, also known as tamoxifen - a "serm"
Which more or less blocks estrogen binding to your nipples (preventing gyno/ flare ups) and kickstarts your natural test production to put it simply.
Can't really comment on alphamax xt as I haven't researched or read into it. Assuming it's some sort of natural test booster? In which case I'd just follow the directions on the bottle lol
Hope this helps!