Port wine kit, can I use liquid yeast and do I need to fortify with brandy

I just received my chocolcate rasberry port kit. I didn't realize the kit came with yeast so I had already purchased the

Wyeast 4767 liquid pack
Flocculation: Medium-low
Attenuation: NA
Temperature Range: 60-90°F, 16-32°C
Alcohol Tolerance: 14% ABV

My question is should I just use the 2 pacs of generic dry wine yeast they gave me or use my liquid yeast instead? If I use the liquid yeast will I have any problems fermenting out...I have heard this kit can be difficult to ferment out? I do have temperature control ability so I can keep it on the high side 75-78 degrees.

Next question is with fortifying. The instructions just say use f pack to finish the wine before bottling. I assume there is something in there that will kill the yeast or maybe its just the ABV that kills the yeast? Does this mean that I should not fortify the wine with brandy/everclear?

Starting this today and was hoping to get an answer....any suggestions?

Can you show the kit? I feel like you would be better off using the dry Port yeast if that is what comes with it. If it is just a dry wine yeast and not a specifically high gravity yeast then I would guess the Wyeast probably.

I believe it's Red Star "cotes des blanc". Says 12-14% ABV. It could be premier cuvee but I think it's the other.

I ended up having the Premier Cuvee dry yeast in my kit (2 packs). The ABV threashold is 18% which is 4% more than the liquid yeast. I actually called winexpert the maker of the kit to ask them my 2 questions. For the yeast they highly recommended using the dry yeast packs given and not the liquid yeast. They stated that they do extensive testing on the kit and to follow the instructions as described for best results. She said the liquid yeast I had might not break down the sugars the same way. I ended up using the dry yeast instead.

For the fortifying here is there response:
Thank you for your contact. Yes, you are correct - the yeast quits after it has converted all the sugars into alcohol and the gravity is constant at the reading as per the instructions at stabilizing. As long as there is a source of fermentable sugar and live yeast cells in the wine, nothing will prevent them from eventually refermenting the wine, unless there is also a sufficiently high alcohol content to help kill the yeast cells.

Although some people elect to fortify their Winexpert Port, we don't recommend it and therefore we don't recommend a particular brandy. Whatever brandy you use will have an impact on the flavour.

You should also be aware that commercially produced Port is not fortified with brandy. It is fortified with aqua ardiente, a 200 proof grape spirit. This raises the alcohol content without diluting the flavour. Commercial brandy is usually 80 proof. For every fifth of brandy you put in, you are actually putting in about one and a quarter cups of pure alcohol, and two cups of water. It won't drive the alcohol content as much as you might think.
Fortifying spirit is best added at fining/stabilisation. The alcohol in the brandy can coagulate the proteins in the wine, but if it is added at stabilisation, these proteins will settle out, and won't cloud the wine later.
Fortification can be calculated using the Pearson Square formula:
A (alcohol content
of fortifying spirit)
D (C-B) the difference is the fortifying spirit required
C (desired alcohol content
of fortified wine)
B (alcohol content of existing wine)
E (A-C) the difference is the part of wine to be fortified

It is necessary to know the percentage of alcohol of the spirit to be used for fortification and also in the wine being fortified.
Example: The fortifying spirit has 40% alcohol content, the base wine has 15%, and you want to increase it to 20%.
Subtract B (15) from C (20); the remainder D (5) are parts of spirit to be used in the mixture. Subtract C (20) from A (40); the remainder E (20) is parts of wine to be used. You will need 5 parts of spirit to 20 parts of wine to bring the mixture up to 20% alcohol by volume.

I would like to experiment on my first batch. I plan on bottling 2 gallons of the port with no fortifying of spirit as described in the instructions and 1 gallon with fortifying with Everclear grain liquor (75.5%ABV).

Based on the formula below I get:

A=75.5
B=15 (I assume it will be close to 15% for this calculation but would obviously calculate at final gravity)
C=20
D=5
E=55.5

So, 5 parts spirit in 55.5 parts wine or 5/55.5= .0900 or 9%. If my final volume of port to be fortified is 1gallon or 128 oz then I would need 128*9%=11.52oz of Everclear needed to reach 20%ABV for that 1 gallon. Can anyone confirm for me that I did this calculation correctly?

Your calculations are correct based off of your formula. I made the CRP kit and fortified 1 gallon with 5 oz of brandy, just what I preferred "to taste". Had no issues with the wine. Might consider using grappa, but I think you will be fine with the Everclear you are using.