what are the side effects of taking it?? - the most common one would be gaining a bit of weight/your boobs growing. Your periods usually become lighter and shorter though, which is good. There are tons of side effects that are possible, all will be listed on the leaflet of your pill.
how does it work exactly (sorry this may sound really thick - but just want to clarify i understand what it does and how it is used properly) ?? - again, it's on the leaflet of your pill, or ask the nurse/doc.
does alcohol effect it in any way? - nope, unless you throw up within a few hours of taking it.
do you have to still use condoms when on the pill? - no, but unless you and the guy have been tested for STDs it's probably a safe/good idea.