No. Texas law does not have a status called legal separation. If you and your spouse live apart, you remain legally married until a court signs a divorce decree.
That surprises many people, especially those who have moved here from another state or country. Living apart does not by itself decide who keeps the house, who the children live with, or who pays which bills.
If a couple needs court orders while a divorce is pending, the court can enter temporary orders. Those orders can address issues such as children, support and property until the case ends.
A few timing rules also matter. To file for divorce in Texas, one spouse must have lived in the state for the past six months and in the county for the past 90 days (Family Code § 6.301). A court generally cannot grant the divorce until the 60th day after filing, with limited exceptions tied to family violence (§ 6.702).
This article is general information, not legal advice for your situation.