I do my development work and run most of my agency (with multiple employees) with Linux. For some of the business things that most people don't assume Linux can do, I use:
1. Xournal to annotate PDFs (aka sign contracts without printing them and scanning them back).
2. LibreOffice of course for most document related work
3. OBS Studio for recording webcam videos along with screen sharing
4. Audacity for audio editing (heck, I used this even when I was on Mac OS X)
5. Technically I've tried video editing with OpenShot, but do find myself back at Final Cut Pro X on my now 6 year old Macbook Pro for that for now
6. pdfsandwich and Tesseract OCR for OCR/turning PDFs into searchable files
7. Chrome/Firefox are both first class and run all the modern day web application stuff
8. Tons and tons and tons of command line stuff that Linux is well known for
9. QEMU/KVM for hosting arbitrary virtual machines with almost native performance
10. GnuCash for double entry accounting for personal and volunteer society finances. I used GnuCash for a while to run the S Corp accounting when we were on Freshbooks and Harvest, but we've since graduated to QuickBooks Online for better invoicing and CPA office professional services support.
11. GIMP for photo editing
12. Inkscape for messing around with vector graphics
Once you get past locating the tools to do your job. Linux has everything.