Hello Preston,
This forum is a user-to-user support forum. My name is Charles and I am a fellow user with decades of experience using Microsoft Word. I have written extensively on using Word and have authored help articles on the Microsoft site.
Word 2010 and Word 2021 are the same when it comes to changing the checked symbol (and unchecked symbol). The screenshot below is from Word 2010. You are not required too use Wingdings but you can. There are several Wingdings fonts. Try scrolling in the Fonts drop-down. They should be on your computer. https://docs.microsoft.com/en-us/typography/fon....
Once you have such a checkbox, you could save it as an AutoCorrect or AutoText entry for future use. The process to find symbols that you want to use can be tedious, I agree. Again, it has not changed since the introduction of the Checkbox Content Control.
I hope this information helps.
Please let me know if you have any more questions or require further help.
You can ask for more help by replying to this post (Reply button below).
Stay well