According to the information you have provided in the ticket, you are experiencing the performance issue only when you are browsing the Sitefinity backend.
As I have replied in the ticket the performance may depend on the environment settings and the specifications of your machine.
Since you have created the Sitefinity project in your laptop what I suggested in the ticket is to try to test the project on another environment or if possible to set the project on your desktop machine and check the results.
In addition to this, please note that normally the Sitefinity backend is slower than the Sitefinity frontend since there are a lot of requests made and a lot of processing going on in the Sitefinity backend.
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