So I am using a graphine os phone and have so far had a really good experience with it but I need to put parental settings on a google pixel 5a and it is not in the settings menu. I assume that's because its a google related thing, so is there a google service app that will add this setting back in?

TLDR: Google Family Link will not work, because it requires some very dangerous permissions, which are only granted when Google Play Services is a system app (not the case on Graphene).
Use something like TimeLimit.io (open-source, on F-Droid) to achieve similar control.

I don't think Google Family Link will work on Graphene, even after installing Sandboxed Google Play. That's because it messes with some system options, which no regular apps should ever have access to. Google Play Services being a system app (on stock Android) makes this work, because system apps have elevated permissions. This isn't the case on Graphene, because, as the name says, Sandboxed Google Play Services are installed as a user app, and don't have any more access than what you give them as a user app.

    GGORG Hello, I use Google Family link with GrapheneOS with no problem.

      Eirikr70 But does everything work? I've seen that Family Link refused to even start om Graphene before, so maybe the situation has changed... Still, I recommend something like TimeLimit.io

        GGORG Do you have first hand experience with TimeLimit?

          GGORG Family link runs fine with GrapheneOS together with Google Play but I use it very little since I hate limiting my daughter (I set it up in order to have her mother accept her having a phone). I set up my daughter's phone before I switched to GrapheneOS, so I had to stick to Google for that. I don't know about Timelimit so I wouldn't give any advice, but any solution without big G is to be preferred.