The overflow is just that, it comes out when the fluid level reaches the top of the tube so yeah, something is in the float valve making it leak...or it is warn out. This is usually just one, not both though at the same time unless both got trash the same time. Open the drain ports and let the valves open fully and try starting it. This will give you the best chance to flush-out what's there if possible without carb removal.
Why are you showing us a pic of the inside of the air filter?
The only philips-headed screws there are on the bottom of the bowl. They don't come completely out as they open a port to the drain hole next to the overflow port..which should have tubes on it where the drain does not.
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