If you have a will, you still need to go to probate unless you have another way to pass your assets to the next generation or to your heirs.
A will really is just an expression of your wishes regarding where you want the assets to be distributed and how you want people to get them when you pass away. But a will has no meaning until you die and therefore you just own everything in your own name until your death and a will just says where it goes after you pass away.
Wills go through a probate court process when you die. Just because you name an individual to receive assets under your will, it doesn’t happen automatically. And what goes through a probate court process are assets that you own in your individual name, without a beneficiary designation.
If you owned a home or if you owed a car, or if you owned a bank account, and it was solely in your own name, and your will said where you wanted those assets to go when you died, the court would oversee that process and make sure that your wishes were followed.