Check the following to tone your triceps! If it's to difficult for you then try it with your feet flat on the floor and not on the bench.
https://www.youtube.com/watch?v=sxrjzBl1LC8
I agree with CuteNsweeT
Start increasing your strength training. Push ups, as were discussed in a previous post of yours, work your overall arms and shoulders... bicep curls (placing your arms to your sides and in front of you with your palms facing away from you and the curling your arms upward to make a 90 degree angle), tricep kickbacks (bend your knees a bit and lean forward to try and make your back a straighter line then put your arms at a 90 degree angle... push your hands and weights up and back to make your arms almost straight)...
You cannot spot-reduce fat (unless you get surgery, lol). You have to lose fat/weight overall in order to lose it from certain places. Once you have lost weight (and even as part of your weightloss regime) you can do toning exercises that will shape and define your muscles. Dips are good for underarms, if you don't have weights to use.