We can delay updates, but no one can permanently stop them.
Commencing with Windows 10, regular updates are arguably one of the most important features of Windows. Microsoft's goal is for every Windows user to have a supported version of Windows.
If updates 'mess up your computer' you have to ask yourself why the great majority of Windows 11 users can install updates but not you.
Without knowing anything about the problems you experience, no one here can help. However, in general terms, updates to Windows are tested on supported configurations. The farther away your computer is from a supported configuration - e.g., unsupported modifications, obsolete hardware or software, incorrect system settings - the greater are the chances that an update will cause problems.
Many so-called solutions for permanently stopping updates have come and gone over the years, and they all eventually fail or cause problems because, fundamentally, permanently stopping Windows updates is not supported.
FWIW I routinely delay new versions of Windows by 90 days (so I won't get version 26H2 until next year) because this gives me an opportunity to learn about it and see how it's performing.