Hey thanks a lot for responding so soon, so just to make sure we're on the same page i just buy the 6p, cut my sim card to nano and plop it in and it would work just fine without the need for anything else? And also i have looked into Project Fi but dont really understand what it does and what the point of it would be. Why not just use my standard carrier services? Thanks again for all the help im really greatful
Cutting the SIM card should work, though the Micro SIMs are actually a bit thicker than a Nano SIM, so it can be a tight fit and maybe even will need a bit filed off the top. Often, it is just easier to go into a T-Mobile store and ask them to swap your current SIM for a Nano.
As for Project Fi, it works well if you don't use a lot of data or are on WiFi a lot of the time. If you have an Unlimited plan, or use BingeOn or Music Freedom a lot, it is likely not a good deal. The advantage bjrosen was talking about is that Project Fi uses both the T-Mobile and Sprint networks, switching you to whichever has a stronger signal where you currently are using your phone. So, if you are in a place where T-Mobile doesn't have coverage but Sprint does, you phone can switch to Sprint and you can keep using your phone like normal.
The other "advantage," at least for those that don't use a lot of cellular data, is that you only use the data you pay for. When you sign up for Fi they have you get a "plan" by estimating how much data you will use each month. They charge $20 for unlimited talk and text, then $10 per GB of data; so if you typically use 2GB a month, you will pay $40 when you start your service (it is actually charged about 10 days later). The next month, if you only used 1.569 GB of data, they will credit you $4.31 for your unused data -- meaning the next month your bill will only be $35.69. If the following month you use 2.5 GB of data, you will still have high speed data the whole time but you will pay for it at the normal rate (no overage fee), so you'll pay $45 the next month.
It is a nice service for those that don't use a lot of data; particular for people who are paying $50-100 for their current cell phone plan but only use a few GB of data each month. An other disadvantage is you have to use one of the newer Nexus phones -- either the 5X, 6, or 6P. While that may change in the future, I'd plan that any upgrade will have to be for a newer Nexus phone.