I'm looking for a way to get the entire options chain (All options expiries) for a particular stock in excel without manually copy pasting anything. It does not have to be real time and I will only be searching for 1 stocks options at a time. A free method would be ideal.
There was a recent thread discussing this historic options data That data source mentioned there is commercial, though reasonably priced. Their data in CSV format readily ingestible by Excel. One note of caution is options' daily closing quotes are not always accurate.
From e.g. the CBOE web site you are able to download a full table of option quotes (delayed) for a specific stock (menu quotes - delayed quotes).
Take it from there, appply data manipulation (Excel VBA, R, Python..) to the extent needed and then you should be be able to end up with the desired result. This wouldn't be a simple copy & paste procedure; it requires some effort on your side but - there's no free lunch.