Yes, you may file as Married Filing Separately even if you filed jointly with your spouse in previous years. However, Married Filing Separately is generally the least advantageous filing status if you are married.
You can compare filing jointly vs. separately with TurboTax's free calculator TaxCaster. It will give you the estimated tax differences when filing either way.
Or, if you are using TurboTax Online version of the software, you will need to create a different account with different user IDs. So one for each spouse and then one for filing jointly. You can then compare total taxes due filing separately to the amount if you file jointly. You can click My Account in top right and then Save & Sign Out to save your return.
Many married couples find it best to file jointly since that usually provides the larger refund and you don't have as much due in taxes.
You can see in more details here Is it better for a married couple to file jointly or separately? why it's better to file jointly. And you will find more details on why you’d want to file separately on that page as well.
When you file separately, your tax rate is higher and you won't get to claim these things:
