Hi @Unhandled_Exception
Sorry to hear that this has been challenging for you.
I just wanted to come back and maybe provide a quick overview of how to generate the token in simple steps, once you get the gist of it, it is pretty straightforward.
Once you have your Server-to-Sever OAuth app created with all the basic information and scopes in your account, you will have a set of credentials that will be used to request the access token:
- Account ID
- Client ID
- Client Secret
With these credentials, you will make a request to the Zoom Oauth endpoint in order to get an access token.
As you mentioned you were using Powershell, I have created a request with my credentials using Postman and grabbed the code-snippet for Powershell and it looks like this:
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Authorization", "Basic {myClientID}:{myClientSecret}")
$response = Invoke-RestMethod 'https://zoom.us/oauth/token?grant_type=account_credentials&account_id={myAccountID}' -Method 'POST' -Headers $headers
$response | ConvertTo-Json
And this is the response I am getting:
Once you get this reponse, you will use the access_token the same way you are using the JWT token.
The only thing that changes is the way you generate the token, for the Server-to-Sever OAuth app you request a token to our OAuth endpoint using account credentials, whereas with the JWT app you generate a token using your API key and API secret.
Lastly, here is a video that I created a while ago on how to set up a Server-to-Server OAuth app step by step and also how to make requests via Postman.
Please let me know if this helped and feel free to ask as many questions as you would like, I am happy to guide and provide you with support on this 
Cheers,
Elisa