Do not know who you spoke with but there is no way to divide your filing status on a tax return between married and single. The information you received was grossly incorrect.
On your 2022 tax return that you file in 2023 your filing status would be Married Filing Jointly since your spouse passed in 2022.
On your 2023 tax return that you file in 2024, assuming that you do not remarry, your filing status would be Single.
