Critical problem in importing scripts

Hi, I have been working on a project for more than a year. All good in unity 2018 and 2019 versions, until version 2019.2.1f1. I did the same as always, letting the editor reimport everything and it seemed fine, until in all the scripts of my project the following message appeared: "The associated script can not be loaded. Please fix any compile error and assign a valid script ". I tried the method of separating all scripts from the project folder and reimporting everything. It worked, but now all the scripts associated with objects and objects associated with scripts, could not find your script (I don't know if I explained myself well). Searching all scripts and associating them all again is not an option. I have hundreds of scripts and thousands of objects in my project and I can't waste time with that. I went back to my backup in an earlier version of unity, but when I downloaded some changes from Unity Collaborate, I began to receive the following errors:

 Library\PackageCache\com.unity.test-framework@1.0.13\UnityEditor.TestRunner\TestLaunchers\RemotePlayerLogController.cs(14,36): error CS0246: The type or namespace name 'DeploymentTargetLogger' could not be found (are you missing a using directive or an assembly reference?)

 An error occurred while resolving packages:
   Project has invalid dependencies:
     com.unity.2d.sprite: Package [com.unity.2d.sprite@1.0.0] cannot be found
     com.unity.2d.tilemap: Package [com.unity.2d.tilemap@1.0.0] cannot be found
     com.unity.modules.androidjni: Package [com.unity.modules.androidjni@1.0.0] cannot be found
     com.unity.package-manager-ui: Package [com.unity.package-manager-ui@2.2.0] cannot be found
     com.unity.timeline: Package [com.unity.timeline@1.1.0] cannot be found
 
 A re-import of the project may be required to fix the issue or a manual modification of C:/Users/jrcon/OneDrive/Escritorio/Adventure (Unity)/COPIAS SEGURIDAD/Juego Plataformas experimento sistema dialogo - copia/Packages/manifest.json file.

 Library\PackageCache\com.unity.test-framework@1.0.13\UnityEditor.TestRunner\CommandLineTest\LogWriter.cs(17,67): error CS0246: The type or namespace name 'DeploymentTargetLogger' could not be found (are you missing a using directive or an assembly reference?)

 Library\PackageCache\com.unity.test-framework@1.0.13\UnityEditor.TestRunner\GUI\IGuiHelper.cs(10,9): error CS0122: 'IFileOpenInfo' is inaccessible due to its protection level

 Library\PackageCache\com.unity.test-framework@1.0.13\UnityEditor.TestRunner\GUI\GuiHelper.cs(19,19): error CS0122: 'IMonoCecilHelper' is inaccessible due to its protection level

There are errors from JetBrains Rider because I used Rider 2018.3 before, but I decided to uninstall it to change it for Visual Studio 2019 Enterprise , but still uninstalling it, it seems to give plugin errors.

 Library\PackageCache\com.unity.ide.rider@1.0.8\Rider\Editor\Discovery.cs(7,13): error CS0234: The type or namespace name 'CodeEditor' does not exist in the namespace 'Unity' (are you missing an assembly reference?)

 Library\PackageCache\com.unity.ide.rider@1.0.8\Rider\Editor\PluginSettings.cs(5,13): error CS0234: The type or namespace name 'CodeEditor' does not exist in the namespace 'Unity' (are you missing an assembly reference?)

 Library\PackageCache\com.unity.ide.rider@1.0.8\Rider\Editor\RiderScriptEditor.cs(5,13): error CS0234: The type or namespace name 'CodeEditor' does not exist in the namespace 'Unity' (are you missing an assembly reference?)

 Library\PackageCache\com.unity.ide.rider@1.0.8\Rider\Editor\RiderScriptEditor.cs(184,12): error CS0246: The type or namespace name 'CodeEditor' could not be found (are you missing a using directive or an assembly reference?)

 Library\PackageCache\com.unity.ide.rider@1.0.8\Rider\Editor\ProjectGeneration.cs(286,17): error CS0246: The type or namespace name 'ResponseFileData' could not be found (are you missing a using directive or an assembly reference?)

and it also gives me Visual Studio errors ... this is very strange

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\VSCodeDiscovery.cs(7,13): error CS0234: The type or namespace name 'CodeEditor' does not exist in the namespace 'Unity' (are you missing an assembly reference?)

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\VSCodeScriptEditor.cs(8,13): error CS0234: The type or namespace name 'CodeEditor' does not exist in the namespace 'Unity' (are you missing an assembly reference?)

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\VSCodeDiscovery.cs(12,9): error CS0246: The type or namespace name 'CodeEditor' could not be found (are you missing a using directive or an assembly reference?)

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\VSCodeScriptEditor.cs(12,39): error CS0246: The type or namespace name 'IExternalCodeEditor' could not be found (are you missing a using directive or an assembly reference?)

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\VSCodeScriptEditor.cs(39,70): error CS0246: The type or namespace name 'CodeEditor' could not be found (are you missing a using directive or an assembly reference?)

 Library\PackageCache\com.unity.ide.vscode@1.0.7\Editor\ProjectGeneration.cs(573,25): error CS0246: The type or namespace name 'ResponseFileData' could not be found (are you missing a using directive or an assembly reference?)

and many more errors from code editors.

I demand a solution from Unity developers. And if someone could help me, I would greatly appreciate it. Thanks and I wait for answers.

PS: I'm sorry for my English, but it's not my native language :/