Having problems with my lawn mower.?

some mowers have an inline fuel filter. google a manual for yours and check. If you have one, take a look at it, most likely plugged. also, put two capfulls of methyl hydrate in a full tank of fuel, this will help with any water that may have gotten in. another thing i would do, that is cheap, is to replace your spark plug, and ensure your air filter is clean/dry.

sounds like water in the fuel , but had mechanic say that fuel line antifreeze wont work because the water actually gets stuck in the carburator , take carb off and clean best you can

Better take it to a mechanic

Bob has it right.