An iPad with only 16GB internal storage, with iPadOS13 installed, is going to struggle with space.
If a high proportion of your used capacity is attributed to “other”, you may have some corrupted (or heavily fragmented) files consuming space.
Assuming that you have already deleted unwanted files and Apps, the easiest and most effective method of resolving this problem is to first ensure that you have a full backup of your locally stored files - and then restore your iPad to factory settings:
How to back up your iPhone, iPad and iPod touch – Apple Support
Restore your iPhone, iPad or iPod to factory settings – Apple Support
At conclusion of the Factory Restore process, you have the option of restoring your data and settings from your iCloud/iTunes backup.
I hope this information and guidance proves to be helpful in resolving problems with your available iPad storage space.