tcblaunch.exe is a real Windows component, the “Trusted Computing Base launcher.” It’s part of the secure-boot and virtualization security features (Secure Launch / VBS). The genuine copy lives in C:\Windows\System32, and Windows never puts it in Downloads. May be something you downloaded or ran put it there.
Don’t restore or run the file. If it’s still in Protection history, open the entry and note the threat name (e.g. Trojan:Win32/...) and the date and time.
Look in Downloads for the archive, installer, or tool that came with it, especially cracked software, game mods or cheats, “driver fixers”, or anything from Discord or YouTube links. Delete it.
Run a second opinion scan, such as Malwarebytes Free or Microsoft Safety Scanner.
Check persistence. Open Task Manager, then Startup apps, and look for anything unfamiliar. Also open Task Scheduler and look for odd tasks. Run autoruns from Microsoft Sysinternals if you’re comfortable with it.
If you actually ran something from that download, change your important passwords (email, banking, Microsoft account) from a different, clean device, and turn on two-factor authentication.
If anything still seems off, such as unexpected processes, disabled security settings, or new startup entries, back up your personal files and consider resetting Windows with “Remove everything.”