Im new here.
So I'm a bachur, 20yrs old.
It started when I was 11 or 12 when I had no idea what was happening.
Then once I started I found it hard to stop. Fastfoward 8 years I'm 20 and still have the problem of z"l and also watch P***. 
The thing is I only do z"l and watch P*** when I have an abundance of spare time. For example I come home for bein hazmanim and there isn't much to do so I do z"l. 
I have a filter on my phone but there's always other phones in my house. 
If anyone has advice please let me know.
Thanks in advance.

Hey Welcome!!!!!!
Are their any jobs available where you live? Or any camps you can go to or work at?

Last summer I worked at a camp and was clean for 2 months then when I came back I adventully started again.

Welcome and join the recovery club!

There are a number of tools available on this site that are worth trying out. For starters maybe the taphsic method can work for you, if you have multiple unfiltered devices. With that you can try the 90 days challenge, which gives some competitive motivation. Of course there is always this forum, where you will get support and moral grounding! The more I come here, the more it helps me stay focused and clean. 

Behatzlocha
WBF

Tell everybody that you have used their phones to look at inappropriate things on the internet because on yours you have a filter, and that they shouldn't lend you their phones.

You can tell your parents and have them pass it on discreetly, you don't necessarily have to make an announcement.

You can explain that on your phone you don't have a problem because you have a filter, but that by the same token you cannot handle it when the filter is not there.

Unfortunately other people in your family probably have their own struggles on this that they are ashamed to talk about as well.

Hey that is actually huge. You know what sets you up for failure and for success. 

Empty time is your nemesis, as it is for all of of. As it says, "beautiful is Talmud Torah with Derech Eretz for the toil of both of them forgets sin" as well as, "boredom leads to sin". I am talking to myself as well. We both need to set ourselves up that we are being productive, have structure, and do not have too much empty time. 

Obviously we should also make plans for how to survive on days when we have nothing happening and a lot of empty time; just like we should have a plan for how to escape a building if there is C"V a fire. However that does not mean that we should enter a fire for no reason. On the contrary our emergency plan is how to get out of the building. Same thing here by shmiras Einayem, part of our plan should be how to get out of a bad situation where we have too much empty time... The answer find a productive way to spend our time. 

HI welcome  its great that you are here trying to deal with this.
I can relate - when I was a bochur ,the between times when I didnt have much structure was when I went crazy with this stuff again and again until I felt like an empty shell shivrei keilim - in fact even once I got married this  persisted ( though I have less free time ) particularly  when i had to stay home to watch the children at night...  yet, right now im watching the kids while my wife is away for a few hours  sitting on my couch with a computer on my lap and Im not even thinking about hitting incognito - im getting chizuk on GYE !!!  nuts ! never could imagine this scenario when i was your age ! Boruch Hashem with the help I got from this site  I am in a way better place and much more capable of not getting pulled in during boring times.

Hatzlachah I hope you too find success.

Welcome!  yes, that is definitely a problem.  Stay as busy as you can will definitely help. check out the handbook. keep posting.