I have planned to make a smart parking project using object recognition. But, when I tried to verify the program, it shows 'POSITIVE' was not declared in this scope. I deleted all old LiquidCrystal_I2C.h files. Even though it is showing the same error. Please help me.
There are multiple libraries that contain a file named LiquidCrystal_I2C.h. The code you're trying to compile is written for a different library than the one you have installed.
Can you suggest me any library
When I try to upload program to my device. It shows candidate expects 0 arguments, 2 provided. Please help me. 
When you encounter an error you'll see a button on the right side of the orange bar "Copy error messages". Click that button. Paste the error in a message here USING CODE TAGS (</> button on the toolbar).
Please post your full sketch. If possible you should always post code directly in the forum thread as text using code tags (</> button on the toolbar). This will make it easy for anyone to look at it, which will increase the likelihood of you getting help. If the sketch is longer than the forum will allow then it's OK to add it as an attachment. Don't put your code in some external file service like dropbox, etc. We shouldn't need to go to an external website just to help you. I do feel it's reasonable to post a link to code hosted on GitHub or similar code hosting sites since that's an platform specifically designed for this sort of thing
Please always do a Tools > Auto Format on your code before posting it. This will make it easier for you to spot bugs and make it easier for us to read. If you're using the Arduino Web Editor then you will not have access to this useful tool. I recommend using the standard Arduino IDE instead.
When your code requires a library that's not included with the Arduino IDE please post a link (using the chain links icon on the toolbar to make it clickable) to where you downloaded that library from or if you installed it using Library Manger (Sketch > Include Library > Manage Libraries) then say so and state the full name of the library.
Can you suggest me any library
I can recommend the hd44780 library for I2C LCDs.
I didn't mean to specifically endorse the library at the link I provided, since I've never used it. I only meant that I believe it's the one that will work with your existing code.
I would certainly take a look at that library groundFungus recommended if you don't mind adapting your code. It likely wouldn't be too difficult to do.