Better start off with the basics. Link in my sig for skill point allocation guide.
Secondly, a multi vector prom is just a prom with the MVAM. Build it like any escort and you should be fine.
-you can use whatever weapons on an escort and still kick ***. Recommend try a array, dbb, dual cannon, Torp setup in the fore, supported by 2 turrets and a Torp in the rear. Weapon type is up to you, but be advised, as in my guide, Phasers, disruptors, photon and quantum torpedoes cost less to skill up and do the same damage as higher-costing weapon skills do. However, they're known common choices in PvP and can be built against.
-The MVAM escort has a different BOff load out compared to the Advanced Escort, which can MVAM if you have the MVAM console, so BOff power choices differ between them. Generic escort advice would be to have Attack Pattern Omega 3 in the top cmdr slot, followed by potentially another AP Omega or an attack skill like Cannon Rapid Fire or Beam Overload. Having Torpedo High Yield is also recommended, and lastly having a copy of Tactical Team 1 is a good idea, as casting it on yourself makes your ship auto-allocate shield power when under fire, clears up Borg beam-in boarding parties, and adds a small skill buff to weapons.
-engineering powers are also different. Advise would be is to have engineering team and emergency power to shields, preferably two of them, so you can cycle EP to Shields over and over, enjoying the bonus to shield power and the hardened shield resists.
-science powers are the same. You need potentially hazard emitters for the heal-over-time to hull and transfer shield strength for shield heal-over-time. However, you may also choose to add in science debuff powers instead like Tachyon Beam for shield stripping.
Rest is up to you. Don't be afraid to draw up a draft plan and post it here for advice.