Programmatically Process Shared Link Folders and Sub-Folders and Their Contents

To list the contents of a folder nested inside a folder, where you only have the shared link for that top folder, you can use /2/files/list_folder again with the original top-level shared link, but then specify the relative path of the nested folder (e.g. built from the returned 'name' fields), in the "path" parameter.

Here's a real example I just ran to illustrate this:

curl -X POST https://api.dropboxapi.com/2/files/list_folder \
    --header "Authorization: Bearer <ACCESS_TOKEN>" \
    --header "Content-Type: application/json" \
    --data "{\"shared_link\": {\"url\": \"https://www.dropbox.com/sh/tpgtd066g1umb13/AACPWhKNrRujRZHM3p7vXP1Qa?dl=0\"}, \"path\": \"\"}"

# {
#   "entries": [
#     {
#       ".tag": "folder",
#       "name": "another folder",
#       "path_lower": "/public/another folder",
#       "path_display": "/Public/another folder",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:T9-uzcb3s4AAAAAAAAAAFw",
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "traverse_only": false,
#         "no_access": false
#       }
#     },
#     {
#       ".tag": "folder",
#       "name": "some folder",
#       "path_lower": "/public/some folder",
#       "path_display": "/Public/some folder",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:T9-uzcb3s4AAAAAAAAAAGw",
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "traverse_only": false,
#         "no_access": false
#       }
#     },
#     {
#       ".tag": "folder",
#       "name": "one more folder",
#       "path_lower": "/public/one more folder",
#       "path_display": "/Public/one more folder",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:T9-uzcb3s4AAAAAAAAAAHA",
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "traverse_only": false,
#         "no_access": false
#       }
#     },
#     {
#       ".tag": "file",
#       "name": "Getting Started.pdf",
#       "path_lower": "/public/getting started.pdf",
#       "path_display": "/Public/Getting Started.pdf",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:25N5ksooX-sAAAAAAAKbwQ",
#       "client_modified": "2015-01-30T22:53:09Z",
#       "server_modified": "2018-02-16T18:05:53Z",
#       "rev": "191ee4bb0",
#       "size": 249159,
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "modified_by": "dbid:AABL4QRrY7tB9viLgPUqmjkzE6Fe5ujlnlE"
#       },
#       "is_downloadable": true,
#       "content_hash": "c3dfdd86981548e48bc8efb6c4162c76ba961ec92e60f6ba26189068a41fcaf2"
#     },
#     {
#       ".tag": "file",
#       "name": "hello.txt",
#       "path_lower": "/public/hello.txt",
#       "path_display": "/Public/hello.txt",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:25N5ksooX-sAAAAAAAAZYA",
#       "client_modified": "2014-07-02T01:28:43Z",
#       "server_modified": "2018-02-16T18:05:53Z",
#       "rev": "291ee4bb0",
#       "size": 14,
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "modified_by": "dbid:AABL4QRrY7tB9viLgPUqmjkzE6Fe5ujlnlE"
#       },
#       "is_downloadable": true,
#       "content_hash": "82674cafa4320daa280b666af141db2b5bd7db4dff3b69dd91a6caea9e30dafb"
#     }
#   ],
#   "cursor": "AAE77A9T4tcyL7eoj_qL_4C735arjRfDRL8yg-yBRm0LxVYkGlPWtyoihPXig3uKLM8EUBmtUHXDMMnqSzkkbCAeqy3e3IeX2M1rV2NtNKobfmPVVMbK1LiOyn9jI9AsDnF8HHkbgGnlgUw4CvJ1Y1q2pJU-UMzy7qR6K8nYhe2vAcuTfBJmSFgCny3YXlutGJZFubiv9n0-Xmr-i7f5ctcSDUqfw1_sw4mGGmHGIyo3lP_1XJRD9DOOW7WZTYt2Uwr3sVjluPJmO93MUMlu6zEs3pB7xVVTNKk4J24IdcSH2A",
#   "has_more": false
# }


curl -X POST https://api.dropboxapi.com/2/files/list_folder \
    --header "Authorization: Bearer <ACCESS_TOKEN>" \
    --header "Content-Type: application/json" \
    --data "{\"shared_link\": {\"url\": \"https://www.dropbox.com/sh/tpgtd066g1umb13/AACPWhKNrRujRZHM3p7vXP1Qa?dl=0\"}, \"path\": \"/another folder\"}"

# {
#   "entries": [
#     {
#       ".tag": "file",
#       "name": "test.png",
#       "path_lower": "/public/another folder/test.png",
#       "path_display": "/Public/another folder/test.png",
#       "parent_shared_folder_id": "2448313264",
#       "id": "id:T9-uzcb3s4AAAAAAAAAAIA",
#       "client_modified": "2020-06-23T15:46:34Z",
#       "server_modified": "2020-06-23T15:46:35Z",
#       "rev": "5a8c2439cb67d91ee4bb0",
#       "size": 1427,
#       "sharing_info": {
#         "read_only": false,
#         "parent_shared_folder_id": "2448313264",
#         "modified_by": "dbid:AABL4QRrY7tB9viLgPUqmjkzE6Fe5ujlnlE"
#       },
#       "is_downloadable": true,
#       "content_hash": "3c6f88e464f1389ab9fc1a0c28c335e357bc61cf76e10e7bf3f146795e64e9f7"
#     }
#   ],
#   "cursor": "AAFWX5jkg5A6CEUiSOA_lCsuVVHlv2yCFtEkrE9CE4gKFmM3XFjUKL2znkL8V9104ofmyRBuSTIcjl1OOMy6_iuI21csGMIwqapxis_E0azOD7ZMDJQ0tJjMJ39sZ9i-WitNwuu0TDgzJn0UjDr7b9ZFktktVvK9VM5zB3W-3as0YaLmPpb8-4MovsdSiaQ12CSBRClnNVXSOa1T6SSOy3ktqn3SxFyr_fbXlzoevO2RiKthJHgdcFg7BGe89LN4_UKvpPFVGLZFdk6ZX6txXe3fW4Nuvq6k8a0HjLYSJt_yz_417KcLw8-a9sa97OxUYHXjqiDfkKWztFzEX4mWGpky",
#   "has_more": false
# }

Hope this helps, or let me know if I've misunderstood your use case!