Prestashop website Changes -

1 , if you want to change catagories or sub catagories pictures size changes , so go to design and than image setting and than put small defaut and catagories changes 250x250 pixel for small and 350x350 for catagory , remember to regenerate thumnuls and than clear chache amd history ..

2, to change best seller and featured product look below photo 

3. Do not disable module , prestashop account  , basic etc .. if by mistake you did it , so go to php my admin and go to modules and  there inside you can able any module whle putting number 1 , 0 is for disable ..

4 . if you do not want to show product attributes in the website link , so go to classed and there link.php and put there /* in front of text  anchor there is video also https://www.youtube.com/watch?v=NCv9Iwbk6UI