Hello,
what you told is your tab is on password locked and you cannot able to enter in recovry mode.
in this case you have only one option you should flash complete firmware using odin 3.14.1 latest version,
please follow my guidance.
* boot your tablet in to downloading mode,
* goto [https://samfw.com|Samfw] or [https://cestin.net|Cestin]
* enter your tablet model and select firmware
* download odin latest and load all files in odin
* goto option button in odin and select erase nand as in following image and hit flash.
* wait for sometime to install new firmware ther you go…have a good day buddy
[image|2305827]