It sounds like computer science is a subject that really interests you, so a BSc in that subject is a good place to start. Mathematics and statistics are both core skills for computer science, so you will need to devote time to improve your skills in these areas. The Bachelors program should be at a lower level of difficulty than a Masters program, so it should give you an opportunity to develop at a pace that is more manageable for you. Contrary to one of the comments above, if you go into that field, you should not try to avoid the areas in which you are weak --- to the contrary, you should "run towards" those things, and put it in the time to develop your mathematics and statistics to a point where you are comfortable with that aspect of the material.
Setting your sights on a PhD program at this early stage is premature, and for now I would recommend that you see how you find the Bachelors program, and use this to determine if this is a good field for you. I would recommend that you look at your education as a means to develop some skills sufficient for practice, and you will find that opportunities for later work/study will begin to present themselves once you finish your undergraduate degree. Once you have finished your BSc you will be able to see if you can handle a Masters program (i.e., see if you can then handle the mathematics that was giving you trouble before), and from there, who knows. A PhD program is essentially a training program for scholarly research, and there are many other avenues to practice computer science. Concentrate on learning as much as you can in your undergraduate degree, and then you will have a bunch of good options at the end.
From comments: "PhD is in my blood. I can't imagine myself [dying] without a PhD. ... I want to become an instructor of [computer science] in colleges."
With present technology, doctoral-level knowledge of academic subjects cannot yet be injected intravenously, so unfortunately, the traditional arduous journey of research and study is still required. I think academics cringe a bit when we see students express the notion that their life is a failure unless they achieve a particular academic title. That kind of talk suggests a longing for social-status rather than an emphasis on acquiring valuable skills and knowledge.
In your case you have a goal to teach the subject in college, so that is a more useful way to look at it. If teaching at a tertiary level is your goal, then you will need to master the subject and its foundations. By the time you get to the end of a Bachelors degree there may be some opportunities to tutor classes, and this can be a good entry-point into teaching. Many academics begin by tutoring courses for their own professors while they are in the late stages of their undergraduate degree, and this practice assists them to master their subjects and become adept at teaching. Students are usually selected for these positions if they have high grades in their undergraduate subjects, so try to accomplish that, and you will be able to get your first taste of teaching in a college environment.