I wouldn’t expect any breaking changes no. Some of our templates have been upgraded to include newly supported features like ASPNET Core Identity Auth, but using this isn’t required. Do you remember what project template you started with? Eg, is it a plain web application or blazor?
We recommend keeping up to date when you can, some updates might require more work than others, but generally changes required (if any) are very minor. Let us know if you do happen to run into any problems.