Start by learning basic phrases such as "Hello. My name is X", "How are you?", "I'm fine, thank you.", "What is the time?","I'm going to sleep. Goodnight" ,"Where is the nearest coffee shop/restaurant?" etc.
Once you can have a very basic conversation and/or read basic English you might consider learning the grammar behind those phrases. Don't ever bother learning too much vocabulary at first, but it is important to increase it over time. You can also practice your English comprehension by watching English TV shows (optionally with subtitles).