SELECT 
  category_id, 
  parent_id 
FROM 
  cscart_categories 
WHERE 
  parent_id IN(
    759, 760, 761, 762, 769, 770, 771, 772, 
    777, 781, 782, 783, 784, 785, 786, 787, 
    788, 791, 792, 793, 794, 795, 799, 800, 
    801, 802, 803, 804, 805, 806, 807, 808, 
    812, 815, 816, 821, 822
  ) 
  AND category_id != 414

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "34.01"
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "parent",
        "p_category_id"
      ],
      "key": "parent",
      "used_key_parts": [
        "parent_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 55,
      "rows_produced_per_join": 55,
      "filtered": "100.00",
      "index_condition": "(`s2cart`.`cscart_categories`.`parent_id` in (759,760,761,762,769,770,771,772,777,781,782,783,784,785,786,787,788,791,792,793,794,795,799,800,801,802,803,804,805,806,807,808,812,815,816,821,822))",
      "cost_info": {
        "read_cost": "28.51",
        "eval_cost": "5.50",
        "prefix_cost": "34.01",
        "data_read_per_join": "194K"
      },
      "used_columns": [
        "category_id",
        "parent_id"
      ],
      "attached_condition": "(`s2cart`.`cscart_categories`.`category_id` <> 414)"
    }
  }
}

Result

category_id parent_id
763 762
764 762
765 762
766 762
767 762
768 762
773 772
774 772
775 772
776 772
778 777
779 777
780 777
789 788
790 788
796 795
797 795
798 795
809 808
810 808
811 808
813 812
814 812
817 816
818 816
819 816
820 816