You obviously did not take a picture before you took the previous light fitting down. I suggest next time you do, and mark the wires and check the picture as you are lucky this time.
You have connected the supply directly to the switch, so when you operate the switch you are not turning the light off, you are turning the switch on which puts a direct short circuit across the supply which is why the MCB trips.
You need more connector block. The two reds should be connected to each other (Nothing else) The two earths (green and yellow) should be connected to each other (Nothing else) The light is then connected across the two blacks. (The black from the switch ideally should have red sleeving to indicate it is switched live)
Also as I first said, next time, mark the cables and take a picture or two before you do anything else.
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