Lyssaroa
If you want to improve your English skills, I can only second Shantra's suggestion: start watching movies and tv shows in english.
At first it is fine to use subtitles but you should be able to watch and understand everything after a while without them.
I started watching entire shows and movies in English when I was 15 and didn't need any subtitles ever since.
Also reading books in English help a lot to understand the grammar and help memorizing phrases or how words are spelled correctly.
Playing games in english also helps. When I started playing GW2 I simply couldn't stand the (partly) horrible voice actors for certain characters
and switched to English soon after release. (I'm not even switching back to German for my youtube-videos even though I myself speak German)
I also have a second account on a NA-Server, playing with US-people and chatting with them.
Roleplaying is another way of getting the hang of the language. When I was 19 I joined my first english speaking RP-Group on DeviantArt
and made great progress. Since I'm constantly using english it developed into my second "first" language and some people even confuse me
for being British. (Though I think that a native speaker could clearly notice by my pronunciation that I'm not British at all).
By now I'm using more English in my every day life than I speak German though my grammar can be horribly off sometimes, when I try
to talk freely.
But yeah, what I'm trying to say is: the more you use it, the more you get a feeling for the language itself and soon won't need a dictionary anymore
to look up certain words or anything.
I mean - look at the clock time I'm writing that post: it's 05:30 am and I didn't even need to look up a single word or think about how I want to phrase my
ideas and sentences. And I got up at 10 am.
So yeah - practice makes the pro 
And just a small side-note: words like "English", "German", "British" etc. are spelled with a capital letter in the beginning unlike in German,
where these words would be written "englisch", "deutsch", "britisch". The word "I" for "Ich" is also always written in a capital letter.
ALSO (and this is only important to me :D) it is not "tv series" - it is "tv show" - at least Americans would never ever use the word "series" to describe a show.
