help with css!!!!

hi again every1!! i need a bit of help (actually a lot hehe) with css and customizing my page. i rlly suck at this >w< does any1 have some tips, or easy 2 use templates? tysm!!
https://64.media.tumblr.com/2c92d012d14ecf56a72fb50317b56285/tumblr_pk3qg1aMFH1xakhj0o2_400.gifv