Olufemi, it looks you are jumping into ONE with both feet. Imo, this is quite important to ask all those questions, even if you don't get all the answers. I believe ONE's team can answer some of those questions for you with great knowledge of the subject.
Copying options chain. No, you can't copy it. Data feed they use is for ONE, not for you. This means you can not freely use the data for your own purposes other than through ONE.
This is my understanding and you should refer to license.
That said, I've seen attempts to build tools to strip data from ONE. Imo, it's not worth the time, when you can purchase data for 'not so much' in relation to what you can accomplish with that data.
ONE does not have a library of trades (structures) for easy entry. Still entering and manipulating options structures in ONE is not that bad. It's actually quite good in comparison to other, similar tools, you just have to learn keyboard shortcats. Ofc, you still can seek to improve their system or to build your own, custommed for your (changing) needs -- but for this you have to learn how to do it for yourself (hand in hand with datafeed) or keep bugging ONE coders to implement changes you desire.
Or you can 'give up the hope'
All the best with ONE. Don't let it limit your thinking.