Question about Firewall

Hello, I posted a problem here not too long ago. Basically my computer at work attracted a virus. I haven't done anyting differently from the past, and I am concerned about what might have caused the virus. I do know that my firewall was down due to a new phone system that we were installing.

Is it possible to get a virus while the firewall is down without downloading an attachment?
Can you please give me some information on the dangers of having the firewall down?

Also, is it possible to obtain a virus from an e-mail that does not have an attachment?

Thank you sooo much for your time!!!!!
You guys are really the best!!

In technology nowadays, everything is possible.
You can get a malware infection just from surfing the internet alone regardless of a firewall. A 3rd part firewall only acts as protection and warns you of something attempting to intrude, but if you tell the firewall to allow it, it will install whatever the file is carrying.

If you want our help, you will need permission from your works IT department/boss as some work machines tend to have restrictions set, and unfortunately, malware also sets the same kind of restrictions, so in cases of work machines, it's hard for me to tell who's done what.