I currently have the MP shred matrix and friend of mine just recommended me shredzarmy's fat burner.

Nothing much, more or less just eat at a caloric deficit

compounds that may be slightly effective:
EC stack
Clenbuterol
Albuterol
Yohimbine

None of these besides clen will probably provide too significant an increase in metabolic rate/fat metabolism
even clen won't do too much in that regard
the main way these compounds help is through either placebo, appetite suppression, or an increase in energy (which during a cut energy levels will plummet, at least deeper in).. or a combination of.

i need a boost baby

then take your pick
EC is the most forgiving of the 4

Will my stretch marks disappear when i lose all this fat on my gut?

Probably not for years.. they'll just erode over time.

cardio

Fire

Play a sport, it's the quickest way for me; fun and effective

I prefer swimming/soccer/basketball

caffiene