Help me, please! Many synchronization problems and strange behaviors between my Apple Watch and my iPhone

Hello team, hello other community members, I hope you are well.

First of all, I apologize for the forum chosen for this post, but I didn't find another one more suitable for the subject in question. I intend not to forget any detail of my situation, so that you can more easily and fully understand what is happening.

About the devices and operating systems I'm using, I'm talking about an iPhone 11 Pro Max running iOS 18.2.1, and an Apple Watch Series 4 running watchOS 10.6.1

Well, now let's go to the problem itself: it turns out that I had already given up on the Apple Watch, mainly due to the apparent lack of usefulness in my life and the slowness of the series 3 watch I had, when I exchanged it for a series 4 to replace it. Apparently, even according to Apple's diagnostics, it is working perfectly, if not for an extremely annoying issue, the lack of synchronization.

1) The problem already started when I had to pair it with my iPhone, when no matter what I did, the pairing screen did not appear on the watch, it did not seem to obey the iPhone commands, I had several errors and was only able to complete the process after much insistence.

2) After everything was completed, I realized that many settings I make in the iPhone Watch app are not actually executed on the watch, so I have to configure practically everything through the clock settings. For example, if I change the VoiceOver speaking speed through the Watch app on the iPhone, the clock remains at the previous speed, even if it is restarted.

3) It also occurs that the iPhone disconnects from time to time from the watch, even though it is always within Bluetooth range and with everything activated.

4) Finally, it seems to me that the iPhone thinks that my watch is in version 11 of watchOS, when in fact it is not, because it shows some settings that are only available on the new watches, which indicates to me that it may not understand exactly which watch I am using. All this not to mention the battery problems, which has lasted very little, even though it is 88 percent healthy and apparently has never been changed.

It is worth remembering that initially I restored the backup of my previous watch, but when the problems started, I reconfigured it as the new watch, even suffering to be able to pair with the iPhone.

All this intrigues me deeply because it never happened with the same iPhone and the previous watch, considering that this one had an even older system, watchOS 8.

Therefore, I strongly ask anyone who has any idea, even if it seems simple and unimportant, for me to try to solve the problem.

Thank you all very much!