I have petrol in my oil, does this mean my engine is knackered or can it be sorted? its a k707 engine

Maybe have a sticky float needle, had it on my zzr :/ just poured fuel into chamber

Check fuel tap & float valves

As long as you've not been running it like that for a long time you will be ok. You must change the oil and filter before running it again.
Then find what is leaking, the carbs on these bikes are a pain in the arse and if it's not been done you will need to get a set of of rings and seals, LiteTec Blair sells them and they seem to be very good. Google lite Tec and you will find them. They are in Thailand.
Check the fuel tap is shutting off properly too.
The problem with these and other old bikes ( I've just had similar on my TRX 850) is the fuel tap leaks so the fuel tries to flow to the carbs then if one of the 4 float valves also leaks it will slowly fill the engine with petrol!
Symptoms are poor starting like slow turnover of the engine due to the cylinder being full of fuel that won't compress (very very bad) and misfiring / backfiring through the carbs & exhaust.
It will also foul your plugs up which will make the bike run like crap as well.

You will need to get your hands dirty with this but once you find and fix the leak you should be ok.