Hi @RiVaVe ,
My Pleasure!
You have to check your source environment before creating anything on the target environment, why? because the Portal Portal and Power Page are totally different at the Data model but the same from the technical scope.
To check your source environment Data model type please follow the below steps
From https://make.powerapps.com

Then Power Pages

From the Power Page at the home page please select details as shown

Please check you Data Model if it is Standard or Enhanced as shown below

If it is Standard then it is a Power Portal and if it is Enhanced then it is a Power Pages.
If you didn't create the Portal on your target environment before then it will be created by default Enhanced Data model (Power Pages), but if your source environment is Standard Data Model then you have to check my solution here to convert your target environment to Standard instead of Enhanced Solved: Re: Portal Management & Power Pages Management - Power Platform Community (microsoft.com)
After preparing your target environment you need to create new website as shown below

Let me know if you need more clarification.
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