Can you post a picture of the genny with the cover off?
You could pop open the drain on the carb if it has one. Put a plastic bottle under to catch the gasoline. Hit the prime button and see if gas come out.
If it doesnt ive had to remove the fuel line and use a mighty vac to suck the gas back through the line. You could use your mouth. Attach a separate clean piece of tube to the gas line. Clear is best so you have warning to stop when you see the gas.
Since it was running and then ran out of gas. Then wont start. Means either you clogged up the fuel filters or you need to self prime the gas back up. Could be a mixture of both. Might not be priming easily because the filter is partially clogged.
Easiest thing to do is pop the drain on the carb if that model has one. Put a rag or bottle under.