In A Mess

1/im new in LR and have got in a right mess, how can i remove evrything and start again?,

File->New Catalog, but this will cause you to lose your edits on photos, and lose any user-created metadata as well, is that what you want when you say you want to "start again"?

2/ In My "Pictures" folder LR has changed the titles i had on each folder, and just turned them in years iE 2005 2010 2011 etc

Not sure what this means. "Titles on Folder" what is that? Folders don't have titles. Whatever happened and whatever that means, LrC didn't really do this — LrC only does what you tell it to do, so whatever happened is because you told LrC to do this. Perhaps you chose the wrong option at Import which puts photos in a different folder (these options that puts photos in different folders are COPY or MOVE). To keep the photos in the same folders you want to import via ADD.

I thought this was supposed to be fairly easy!!

Lightroom Classic isn't really a program that you just jump into with no knowledge of how the program works, and begin working. Please take some time and read introductory information on how Lightroom Classic works. Here is a free intro e-book: https://www.lightroomqueen.com/ It's totally free, all you have to do is register.

Once you understand how the program works, it is easy. Until then, when you don't understand how the program works, you will have problems (as you have seen).