A family of Microsoft word processing software products for creating web, email, and print documents.
First, a small correction that clears up the search. The buttons are not on the taskbar. They sit in the Paragraph group on the Home tab in Word. They only appear there after a right to left language is enabled. Go to File, then Options, then Language. Under Office authoring languages and proofing, add the language you need, such as Arabic or Hebrew. Highlight it and set it as preferred. Then restart Word and look in the Paragraph group again. If the language is already enabled and the buttons are still missing, check two things. One, that the language is set as preferred, not just added. Two, that you restarted Word after adding it. Word 2021 works the same way here. The buttons do not need a separate Word 2021 setting. If you want the command always in reach, add it to the Quick Access Toolbar from File, then Options, then Quick Access Toolbar, using All Commands. That toolbar can sit below the ribbon if you prefer.
This answer was prepared with help from Muse.
Microsoft reference: Using right to left languages in Office: https://support.microsoft.com/en-gb/office/using-right-to-left-languages-in-office-17d8a34d-36d6-49ad-b765-257cb7cd22e2