Yes you can go inside this store. If they have the screen protector you want they will install it. Call first to make sure they have it and see if you need an appointment for the install. I had them install one about 2 years ago. The guy on the floor in press can install it. You don't need geek squad.
You can call and ask before going in if they have the screen protector. Or you other option is going into TMobile they will install it for you when you purchase one there. I just got one from T-Mobile and they have privacy protectors and regular glass.
Yes store will let you inside if you have mask on and during business hours. I am not sure if they actually will install screen protector for you but most likely they will. They also have Geek Sqaud rofessional services which will most definitely help you with screen protector. My recommendation would be ordering screen protector online and watching youtube video on how to install it yourself as well. Will safe you money on the product and service and you will learn something new and will be safe doing it home instead of going on public.
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