If you have a legitimate .txt file containing Xtream Codes credentials, here is how you typically use it:

Many "XTREAM CODES1.txt" files found online contain . Accessing copyrighted content without a subscription may be illegal in your region and carries security risks, such as malware or phishing from unverified download links. How to Use Xtream Codes Data

Manually type or copy/paste the URL, Username, and Password from your .txt file.