I have this really annoying dissrespectful younger brother. I need advice how to deal with him o.k.?

Plus on top of I have three younger brothers one is 15 I get along with him really good then the difficult one is 14 he hes arrogant hes sweet and still my brother and would do anything for me but he is too short tempered violent lazy arrogant and did i mention lazy anyways I need advice how to confront him and I'm 17 and he doesn't respect me as the older sibling of the family as a matter fact none of them respect me my is incarcerated and my dad is on business trip trust me and my grandmother is too old to handle all of this conflict and on top of everything my 14 year old brother do sent treat me with respect he is SO lay and when ever i confront him or tell to do stuff like shower or take off his nintendo WI he gets violent the other day he st irked me and gave me four sharp cuts on my neck with his long nails hes so fat lazy arrogant violent hes so difficult nobody could deal with except my 15 year old younger brother he bets the difficult 14 year old up the 14 year old is so fat and hard to confront I wish I was taller like the middle brother confront him and could u beleive im already 17 and theres no respect coming form any of my brothers or please I need some serious good advice and help ASAP.