Fergus Casey

Good morning, new to this so here we go, As mentioned above, we are having problems starting the car. The battery was disconnected while the welding underneath was being done, needed more than originally thought so it was disconnected for a few weeks, finished the welding and reconnected the battery, nothing! I do believe the keys were left in the ignition for all or some of the time so is there a particular way needed to get said car going.