The vaccine doesn't prevent the spread.

I think you missed that part. It also doesn't prevent vaxxed from getting the disease, it only dilutes the symptoms.

The point of my response is that whether you're vaxxed or not you're still spreading the virus to unvaxxed people / children / at risk. If you have a child or person at risk around you then you need to quarantine and wear a mask whether you've had the shot or not.

The best thing to do is wear a mask. It helps stop the spread more than the injection does. Wearing a mask prevents others from getting the disease. So if you got the injection but refuse to wear a mask you aren't doing anything to help stop the spread, but encouraging it to spread to those unwilling or unable to get the shot.