IMHO, no matter the manufacturer of a computer, it is not a bad idea to install a fresh copy of Windows to remove any junk they bundle with the computer, such as crummy antivirus programs (Norton/Mcafee) as it slows down the system for little benefit. If the mfg did have any sort of back doors preinstalled (even remote access software specifically for support) this will eliminate them as well.
The controversy with Huawei is mostly political, but, if you are worried about them spying on you, just consider the following: Microsoft bakes telemetry into any Windows device that monitors how you use it. This telemetry collects all sorts of data periodically, potentially including entire memory dumps for crash reports containing any information that was in the programs you had open at that point. Many other software vendors or websites do the same, in fact almost everything does at this point. for example, Google profiles your interests, search history, collects personal information, may tracking your location, etc. For example, if I request to download all of the data Google has on me, I can see every location I physically was at in the past 3 months on a map, as my Android phone tracks this and sends this information to Google throughout the day. Basically, if you are online, you are having data collected about you and it is constantly being resold to anyone who's offering money.