motion capture suit uses?..
They are use for creating animations?
and can they be used to create cutscenes things? like acting dialogues etc.
SORRY IF ITS DUMB QUESTION 
xD
Yes they are used for motion capture animation. There is a lot more work post motion capture to get an animation going such as creating a character, rigging it, baking the animation to the rig, importing into UE4, using persona to create your animation graphs and finally matinee to bring it all together. There are also more advanced topics in all of the stages I just mentioned. Suffice to say just having a motion capture suit is not the key to creating amazing cut scenes, it is but one of the many tools/skills required.
ROGER 
DAT xD
Can you give me a video link or something like tutorials? 
It depends on how you want to capture the animations + which tool you will use (e.g 3ds ,…)
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OOOOOH YEAHHHHH BABY xD
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