If you are unsure you should follow the estlcam guide. It is free, and simple. Fusion is not for beginners. If you follow my guides you will see the numbers I use, or others on their videos. When you get the hang of it and have a sense of things then try out fusion.
I would start with a much smaller bit, 3mm is good to learn with and very forgiving. 8mm is more of a roughing bit.
You will see for all my cuts I use between 12-20mm/s on a 1/8″ bit and vary the depth of cut and spindle speed depending on material. If you are really new to this a single flute bit is even more forgiving and more suited to our high spindle speeds and machine rigidity