Approval workflow

Approval workflow

is there any easy guide to implement work flow where user log a request and is goes for Manager approval? all my users already have reporting to, which is coming from AD. 

When i log a request i see the below error in history 

Action Name : Leave Approval

Message : Traceback (most recent call last): File "set_approval_stage_reportingto.py", line 16, in <module> requestObj = read_file(req_file_path,"request") File "C:\Program Files\ManageEngine\ServiceDesk\integration\custom_scripts\functions.py", line 32, in read_file data = json.load(data_file) File "C:\Python38\lib\json\__init__.py", line 293, in load return loads(fp.read(), File "C:\Python38\lib\encodings\cp1252.py", line 23, in decode return codecs.charmap_decode(input,self.errors,decoding_table)[0] UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 8398: character maps to <undefined>