Hey Scotty,
I have 2015 Nissan Altima SV. 2.5L 172, 889 miles and does the CVT overflow plug help on having the correct measure of fluid on my transmission?
You need to follow the manufacturer's instructions to correctly check the fluid level. CVTs are very sensitive and it has to be right.
The CVT is sealed with no dipstick. However, one of the ways is the overflow plug
does the CVT overflow plug help on having the correct measure of fluid on my transmission?
It's not quite that simple. CVTs have an inspection plug which is used along with specific steps to determine the proper fluid level. Checking an 'overflow' plug alone will not result in a proper fluid level.
one of the ways is the overflow plug
Again, only if you follow the correct procedure, otherwise you'll likely harm the transmission.