President Biden approved major disaster declaration for Texas on Friday, 2/19/2021. That means you can get financial assistance from FEMA, even if you have insurance.
The first step is to call your insurance. If possible, read through your policy coverage first.
Then register with FEMA https://www.fema.gov/disaster/4586. Make sure to documents the damages and repairs thoroughly by taking photos of the damages, the clean-up, the repair, and keeping all receipts. According to FEMA, on average a household or renter can receive between $3k-$6k in assistance. FEMA can help with the cost of repairs and staying at hotels but will not cover the cost of groceries because there was no power at your home.