Oil pan gasket

[solanog]

I want to change the gasket of my 1990 Accord, is this an easy task? The gasket I bought was not a genuine part, it was not available, it's a rubber gasket. Should I need some sort of silicone or just install the bare gasket? One side has sort of very small ribs and the other is smooth which side faces the engine?
What's your advice? Better take it to the shop? I also need to take the oil pan to a shop and "rebuild" the oil's plug thread. Screws torque?

Thanks