the car has bew battery when battery was connected the horn came on but nothing else
Take the car back to whoever installed the battery
I saw this once in a Volkswagen. A coworker at AutoZone installed a new battery but reversed the terminals. Significant damage to the electrical system before I caught the error.
Who installed the battery? First thing to look at is the fusible links in the underhood fuse/relay box.
I don’t have a schematic in front of me but look at the high current ones first; those 30, 40, 50 amp ones.