its the same, my dad lets me use this pc, he did not allow me to do anything suspicious, but i once removed windows, installed ubuntu, then zorin os, and once again ubuntu, all without him knowing. so it is a bit risky, but i am ready to take it, if it goes smoothly.
I certainly understand your point of view. However, I must ask you to understand the point of view of ZorinGroup and the Forum as a whole.
If your father is upset about his possessions being altered- and if he comes here and confronts us for aiding and abetting - it can be quite a show...
Sometimes a person may be far more open to exploring possibilities than you may think. And sometimes, they may not be. The only way to know is to honestly be upfront. Give a good reason why another method may be better. And if they are not, regardless of how we may personally feel about it, we must respect their investments and their property, even if we make a note to ourselves to do things differently with our own investments. Or as a motive to acquire our own.
Others may disagree with me on this. But for me; I must stand by my ethics and what I believe is Right. My gut keeps clenching as I read these posts. It's not sitting with me right, at all.
I have not told any of these before, so i am not getting the courage to speak up.
and @Aravisian my father allows me to do such things, but i don't study properly, and hence he asks me to focus on studies instead of computers. He always says me that if I study, he will let me do anything of my wish, and buy me anything I want.
I know the feeling. 
You know... Studying computers is a form of studying. It's not all about finding your interests, but about ensuring your interests make meaning in your life. You don't have to have a wealthy career from a passion, but having a career out of your passion makes a big difference. We often study hard on the things that interest us, but struggle to study that which is uninteresting to us.
Trust must be earned, but it must be earned by both sides. It takes a lot of trust in a person to be able to trust them with Truth.
during my classes, i always play games instead of studying, hence i lost the trust of my parents, which i truly regret and want to gain it once again, which I know takes very long time.
I think your parents are lucky to have a kid like you 
Yes of course, they know that I am very studious, but as I started to become lazy, my interest in studies faded away. My parents are very sad due to it, I really want to make them happy, but I am also not able to sacrifice my gaming.
Surely, we all need a balance. 
I feel ashamed to make them sad 
I was the same way in school. Nearly failed High School even...
I found many classes just plain boring.
But I had the same trouble - I was making my grandparents (My own parents... were interesting people...) who raised me most of the time pretty upset.
So, I began calculating my GPA, every day. With each assignment, I could calculate the affect it had on my Total GPA. With every day that went by, I was seeing the instant reward (Achievement unlocked) of that GPA climbing.
Before long, I began introducing new challenges, such as seeing if I could make it jump up instead of slowly climb. Extra credit, extra curricular activities... The following year I took Honors classes, since they allowed for an additional GPA point. (Like finding armor with bonuses.)
By graduation, I was on the Honor Roll, straight A student.
All because I used the dumbest method to motivate myself... making my GPA climb just one day at a time...
So guys i am installing ubuntu in another partition beside zorin os, will the grub of ubuntu create any problem with zorin os grub. please answer this as it is my main doubt.
No wonder how you know so much about things 
I think you will only have one bootloader.
Since I never dualboot 2 Linux, you might want to wait other volunteers with this experience to confirm this.
I suppose there is no one here with that kind of experience which i am going to have 
I have booted up to four distros on one bootloader.
Please explain how did it work. my ears are longing to hear it 
Easily- installing the other distro and grub uses the same bootloader. No special steps needed.
damn i didn't know that wow 