Is this drug safe, ? { paracetamol 500mg+50mg diclofenac sodium+ chlorpheniramine+magnesium trisilicate }

No. Too many meds that can combine to cause side effects. Pick one of them and forget the other three.
Safe. Paracetamol is an analgesic, diclofenac is a non steroidal antiinflammatory, chlorpheniramine is an antihistamine and mg trisilicate is an antacid / stomach coating. Seems like this might be directed against cold/allergy symptoms with the trisilicate added to protect stomach against the diclofenac.