Is it ok to eat chicken one day after its use by date?

Yes if has been stored correctly. ie. not already cooked and kept above 4C so that bacteria thrive. If it is slimy and has even the slightest bad smell then toss it out.

That date means "Best if used by" and not "dangerous if used after." For example, Frito-Lay guarantees that the chips in an unopened bag are crispy & fresh until the "best used by" date. You can still open the bag and eat the chips after that date has passed, but there is no Frito-Lay guarantee that they will be crispy & fresh.

Now if we we're talking weeks and months after the "best by" date, you might want to be a bit careful. But one single day? That's not an issue.

you can eat it and you'll be fine