I started my period with 4 active pills left, now my period is near the end, do i take placebo pills or just start a new pack?

Just continue pack : Breakthrough bleeding (bleeding at the wrong time) is very normal on birth control. It happens in about 1/3 of users. Its no big deal and usually self corrects over time. If you are not satisfied or it continues to happen then consider using a different birth control method. It is a common side effect and does not mean something is wrong or that the pill is not working.

Either: Menstrual periods on bcp are drug induced so either approach is reasonable. Most doctors would recommend you just continue the pill pack as it is provided. However, starting a new pack of pills will usually stop menstrual bleeding.