The note that you see written is the root of the chord. So the Bm means that it's a B minor triad. So those notes would be B, D natural, and F#. So B is the root of the chord, D is the minor third of the chord, and F# is the fifth of the chord. Minor is noted by using a small m, or a minus sign - to the right side of the letter which names the note. So we will see Bm, or B- , or Bmin.
The next chord you list is D. Lets assume that you mean that it's a D major triad. Major is usually noted as Dmaj, or DM, with a large M as opposed to the minor chord's small m. Or it might be shown as a D with a triangle to the right of it. Kapeesh? So the notes of the Dmaj triad are D, F#, and A natural.
Next you have an F#m triad. So these notes are F#, A natural, and C#.
Last we have C#7. A "7" by itself, without a major or minor notation means that it is a dominant seven chord. A dominant chord consists of a major triad, with the added minor seventh. So we're talking C#, F natural, G#, and B natural.
The minor seventh is a whole step down from the root. A major seventh is a half step down from the root.
This harmony needs to be played in time to achieve the sound of the tune. Most chord charts have beat markings per measure, indicating if the chord is 1, 2, or all 4 beats of the measure, assuming that we are in 4/4 time. So you play the chord for the alotted amount of beats, then move to the next chord.
Most important note to play in time with the changes? I say just play the root, then move to the next root and then the next. Stay within the amount of beats alowed, the time alowed. You'll see why they are called "changes". You're changing all the time! When you're comfortable with the root, try the root and the third. But you should be able to hear the contour of the tune by playing the roots in the time of the tune.
I posted a practice routine on another thread down in the saxophone section of the forum, I forget what it was called, practice techniques, or something of that nature.
Hope this info helps!