Maybe useful … but let’s stick to the working directory you are familiar with for the next run.
Here is what we expect to see in TWRP
The “Home” position (the back button should get you back here if lost).
At the first run of TWRP, try to test the button marked “Press for log” to check if a log is available.
Please Select Wipe (from top image) → Advanced Wipe → Select the Data partition → Repair or Change File System → Swipe to Execute.
Please Select (similar to ) “Change filesystem”. (Not shown in images).
Select exFAT or tell us what is available, it is not critical.
Swipe from the left to the right to execute.
Carefully get back to
Please Select (similar to ) “Change filesystem”.
Select ext4
Swipe from the left to the right to execute.
Check the log again, can you get a photo, if in any doubt it was successful.
Reboot is found from the "Home" position -> leads to options shown in final image.
I think this phone has no SD card (??) If there is an SD card then Power + Volume UP from TWRP will probably save a screenshot to SD card. (Obviously of little use to us if it saves to device!)
The source of TWRP is LG Nexus 5X.
I suggest you download the file from this link into your working directory Bull