DIYbanter - Repairing/Replacing Exterior Handrails

I have a steel handrail that is attached to concrete steps with what
appears to be an anchor set-up consisting of 4 carriage bolts and a
brackets in which handrail sits. I noticed that the railing is really
leaning to the right. I am guessing that either the base of the
railing has rusted and it is started to fall over or one of the
neighborhood kids was playing on the thing and 'torqued' it pretty
hard.

If I need to replace everything how do I remove the carriage bolts and
anchors from the concrete steps?

If the railing is still good, any advice on how to fix the existing
railing?

Thanks.