Go to www.briggsandstratton.com, use their dealer locator, and find the nearest authorized service center. They will identify the part number needed, and can order one for you.
Most do not have a fuel filter.
probably either a clogged fuel pump or a clogged air filter.
0.030
It also has to be getting gas. After turning it over a few times take out the plug and see if it's wet. If not it isn't getting fuel. Maybe need carb adjustment or new fuel filter or fuel pump if it has one. This may not fix, but it's a good place to start
o.20
it may not have one. If it does it will be located on the fuel line between the fuel tank and the carburetor.
Yes
cawl sistem
There is a fuel pump on this engine. That could be your problem. It is usually bolted on the side of the carb or very close by. It sill have a hose running to it from the intake of the engine. If the diaphragm in the pump has a hole in it the fuel will not pump into the carb.
There is no "gas oil ratio", the 3.5 hp Briggs and Stratton engine is a four-stroke design, oil should NOT be put into the fuel!!!
18 to 20 onces