Log files, mkdir and delete files

I’m testing the exeoutput 2019. I have already generate the .exe of my application and connected to the mysql database. And now I realize that are a lot of errors mainly when I want to delete something or create some directories or to append a photo of an user to an existing directory.
As I´m new with this something, sure I´m missing some configuration.

What should I set to be possible to create the directories as before?
How can I see the log files?
Thank you

What kind of errors do you get?

The errors appear when I try to append some video or jpg or doc to the application. It should internally create the appropriate directory depending on the type of the file.
The errors appear also when I simply want to do an upload of a jpg. I don´t know, why it is happening. Therefore It would be important to see the log files. At least something that I could have a clue.

Is there maybe a configuration that I haven´t done to create the directories. I have seen a post about mkdir issues and there you have talked about runtime version. I didn´t understand that.

How do you append them? With the File Manager? By placing them in the “Data” subfolder?