Bed Rack System

I bought this rack system from another Tacoma owner. Unfortunately, it’s been some time and I’m not able to connect with him.

Great bed rack but not sure where to begin. Eventually, I would like to put a tent on top of it but that’ll be a year and half down the road.

For now, this is what it is but I’d like to do other things than add on a tent.

First, I’m not even sure how things would mount to those bars. Is there an adaptor for it? Where can I purchase them.

Sorry, I just want to use this forum for a source of help. Still very new to the Tacoma and modification seen.

Any help is greatly appreciated.

Thanks,
Joe