Hey @Rado_01203 , Welcome to the 3Community 🙂
Firstly I would recommend going to the coverage checker here to check if the 3 Broadband Unlimited 5G Gold plan is available in the area.
The difference between the two plans is that the Gold plan comes with tech installation. If the Gold plan is available in your area and you have the option to have a receiver installed on the outside of your building then I would recommend the Gold plan however if the coverage checker is also offering you the Silver plan this is also a great plan but you don't need a technical installation.
On the Silver plan all you need to do when you receive the modem is enter the SIM card and plug in the device.