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I presume you are asking about an Engel Australia solar film/panel, SPF90W, and its connection to a 40 Litre fridge made by Engel (or similar.)
Aside from connecting the + connection from the SPF90W, to the + power input of the fridge, and the - connector of one to the - connector of the other (-or in other words, the polarity of the connection being right), there is nothing about the connection that needs to be done right. It should be that simple.
Of course, when you first connect it, the fridge should be turned Off. If it is On, various things might possibly happen, including the blowing of a fuse - though that won't necessarily happen.
Make sure the film is in full sunlight. That's about it. Make sure the connection is good, no dirt in the connector(s). Then turn On the fridge.
If nothing happens, check all fuses - in the fridge, or in the suncontroller. A fuse may be blown, but it might also be absent, quite simply - whether removed as a prank, fallen out, or not installed.
If the fridge does not run at this point, you may have defective equipment in one respect or another, unfortunately. I hope the equipment (wherever the fault is found to be) is still within the warranty or return-exchange period.