Whoever thought that bullying ended when you graduated high school was wrong.
People falsely accuse others of mistakes in order to cover their own, or they take credit for work that another did in order to look good in front of the boss.
There’s also that horrifying co-worker telling tales about everyone, and the boss who has the temper control of a toddler in a tantrum.
All of this leads to a hostile work environment, and a feeling of inadequacy or worse.
The best way to deal with these sorts of issues is to distance yourself as much as possible from the co-workers who behave badly.
And if it’s your boss, you should try to have a member of the HR team mediate.