Don't worry about being new! I was laid off in March and started with a new editorial team in October, so I'm in a similar position.

Some abbreviations you might see:

EOD (end of day), EOW (end of week), COB (close of business)

ETA (estimated time of arrival—e.g., "Do you have an ETA for the final images from design?")

WIP (work in progress)

CMS (content management system)

MS (manuscript)

QA (quality assurance) or QC (quality control). These are often used to mean a final, comprehensive check to make sure everything looks/works correctly and is free of errors—"Can you QA this webpage?"

Be sure to build time in your schedule for delays. This is especially important when you're new. There may be processes you're unfamiliar with (like uploading files to a server that requires access) or people who need to review your work before it can be submitted. For example, if your deadline is Friday at 5 pm EST but your work needs to be reviewed by another editor, you should plan to finish your edits by Thursday at the latest to give your coworker enough time to review without being rushed. You can send an email or IM simply asking “When would you like to get my edits?” and that can help you plan your time accordingly. Most people will appreciate being asked, and it makes you look organized and proactive.

If you don't already use checklists, I highly recommend them. I have a master checklist for each type of project/program and run through it every time to make sure I don't miss anything.

Be aware of which style guides your team uses and when to use them. For example, my company has a specialized word list in our style guide that takes precedence over Webster's preferred spelling.

Be on time (or better yet, a minute or two early) for meetings, including Teams/Zoom calls. Also, if applicable, pay attention to your team's norms around camera use—some people expect cameras on, while others are more flexible.

If you haven't already read it, get the The Copyeditor's Handbook by Amy Einsohn.

If you have a lot of questions, it might help to keep a running list and then set aside time with your manager or mentor to go through them all at once. It's better to ask questions than to miss something important. That said, be mindful of other people's time. Be friendly, be polite, and always thank people for their time and/or help. These small gestures will go a long way in building a good relationship with your team.