how to transfer records from one batch class to another batch class

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  Map<String, Schema.SObjectType> schemaMap = Schema.getGlobalDescribe();
        Schema.SObjectType sobjSchema = schemaMap.get(objtype);
        Map<String, Schema.SObjectField> fieldMap = sobjSchema.getDescribe().fields.getMap();
        List<fieldMetaData> fmdList = new List<fieldMetaData>();
        for (String fieldName: fieldMap.keySet()) {  
            String fieldlabel;
            String fieldType;
            //It provides to get the object fields label.
            fieldlabel = fieldMap.get(fieldName).getDescribe().getLabel();
          
            Schema.DisplayType FldType = fieldMap.get(fieldName).getDescribe().getType();
            fieldType = string.valueOf(FldType);
            system.debug('fieldlabel>>>>>'+fieldlabel);
             system.debug('fieldAPI****>>>>>'+fieldName);
           
            fieldMetaData fmd = new fieldMetaData();
            fmd.fieldLabel = fieldlabel;
            fmd.fieldapi = fieldName;
            fmd.fieldType = fieldType;
            fmdList.add(fmd);
        }
        return fmdList;

here i am getting API  small letters like Test__c as a test__C
can you please suggest me anyone

how to transfer records from one batch class to another batch class