Hello, I'm Greg, 10 years awarded Windows MVP, specializing in Installation, Performance, Troubleshooting and Activation, here to help you.
There's no way using Microsoft Family Safety to set up restrictions on any other than a child account. So you'd have to set up a separate account to do this.
Guide here:
https://www.lifewire.com/microsoft-family-safet...
You might have better luck with one of the other more fully-featured parental controls:
https://www.makeuseof.com/tag/windows-10-parent...
https://www.digitaltrends.com/computing/best-fr...
https://www.pcmag.com/picks/the-best-parental-c...
I wish I had something more to offer, but as it is MS Family Safety is limited and somewhat buggy.
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