Hi FNY. Welcome
For #1 Dispute them both with the CRAs. If it is a duplicate listing then at least one of them should fall off. You can even do a 1 2 punch if you wish.
For #2 You should read
here. Start by sending out the medical dispute letter. (I would send this one separate from the dispute above so pick which one you would like to do first and then wait until the investigation is over before sending your next dispute.)
A lot of times, medical collections being reported are a mistake because insurance wasn't filed correctly or the healthcare provider failed to write off the remaining balance after insurance paid. So it may be fairly simple to remove.
And then for the acronyms.....read
here. That should help you understand the lingo a little better.
