I do not want to give every person on my server the ability to use /player.
How do I specify certain players(without giving op of course)?

You can change the command permission to a number from 0-4 which is a vanilla "op level", with 0 being anyone and 4 being ops able to run critical commands such as /stop.

You can find a summary of what does each level do in the minecraft wiki in the link below, but basically I'd recommend you to use the op level 1 if you just want that, since it gives no extra commands, just "allows to bypass spawn protection" (a feature everyone has forgotten anyway, it is a radius where no-one can build in the spawn if specified).

https://minecraft.fandom.com/wiki/Server.properties#op-permission-level

Those levels are specified in the ops file, I think there's not really a command to change them in vanilla. Therefore, you would give them op level 1 and set the rule commandPlayer to 1.

Thank you. This will be useful.

Another option is to disable player command for all players (ops only), and write a wrapper scarpet app to perform certain allowed actions.

Got two options already for that :)