Question

1. The team usually plays in a 4-4-2 formation. (at a soccer game)

2. two center forwards
(= two strikers)

3. side midfielder (=left midfielder)
two central midfielders
side midfielder (=right midfielder)

4. fullback ( =left back = side back)
two center backs
fullback ( = right back = side back)

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Q1: Is the explanation above is correct?
Q2: Which one is right?
5. full back, fullback, full-back
6. center back, centerback, center-back
7. right back, rightback, right-back

Answer 1

Check out the terminology and the names of the positions here:
http://www.football-bible.com/soccer-info/soccer-positions-explained.html

(I really don't know much about soccer!)