guys,what is the ideal aspect ratio and wing loading for rc biplane and delta plane??

As a rule of thumb, you may design your airplane around an AR of 6 and wing loading of 25g/dm^3. But for biplanes, you need to take care of the fact that two wings doesn't mean that the planform area is doubled because of the interference between the top and the bottom wing. Again as a rule of thumb, consider about 70-80% of the doubled planform area (which is basically 1.5-1.6 times the planform area of a single wing).
Biplanes can be tricky, so I would suggest that instead of designing your own airplane, you should download an existing plan.