Question: My supervisor started the e-mail thread of welcoming me to the team/department. Several team members has already replied (including the boss of my supervisor so I'm extra nervous) with a brief but warm welcome message. I was wondering what is the best way to reply in this thread.

This is my first fully remote role so I am not that familiar with how it works yet.

Would a short reply like "Thanks for the warm welcome, I'm excited to be working with everyone and I'm looking forward meeting you in the upcoming weeks." or Should I be adding my professional background/main tasks of my role/hobbies/etc. ?

Answer: 
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> "Thanks for the warm welcome, I'm excited to be working with everyone and I'm looking forward meeting you in the upcoming weeks."
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> 
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Your suggested reply is perfect. Stop fretting.
You don't need to respond to this email chain at all. It's assumed that you received those welcome messages and possibly read them. If you're not comfortable in replying to them, then don't.

If you do want to reply, then a simple "Thanks everyone for the warm welcomes!" is fine. Depending on the company, you may or may not be prompted by your manager and/or HR at some point to write an introduction note to your coworkers. At that time, you can share that information, like your role, hobbies, etc. It's generally good for the company to prompt you to do that, because it facilitates camaraderie ("Oh, you like LOCAL\_SPORTS\_TEAM? I also like LOCAL\_SPORTS\_TEAM, what do you think about STAR\_PLAYER this season?"), but not every company does. If your manager doesn't prompt you to write an introduction email within your first couple days, you may want to prompt your manager to prompt you to write one, just because it does facilitate camaraderie and that helps create a better work environment. If your manager says it's not necessary, then it's not necessary; some companies are just like that.