Hi, welcome to the boards
You mention edgeguarding with fair, was it a typo? Fair is the only aerial of pikachu that isn't good for egeguard, because it's easily DI-able and more importantly, it has really weak knockback.
Now concerning your problem, you need to think and play smart. This sounds dumb and obvious, but it really is important. From what you describe, it looks like your Kirby opponent always (or very often) use his neutral B to counter edgeguard you. Keeping that in mind, next time you need to edgeguard him, you
know he is going to use his neutral B. So you can simply go back on the stage a little to avoid it and since it's a slow move, Kirby will end up below the stage, where you can edgeguard him. You should try to extend this reasoning to everything. If you notice a habit of his, you then know he's going to do it again in the same situation and you can punish accordingly, even before he does it (since, again, you know he's going to do it).
Now Kirby's neutral B isn't really a threat, as Pikachu, with his great recovery) can go back on stage anyway.
For your second problem, again, since you know he's going to UpB right away, you should change your recovery timing. You should try delaying your second jump or even hold away for a little while, until he misses his UpB.