I purchased home decorations 5/8in bamboo flooring i just need to know what kinda of gun i should use to nail it down and what size nails if anyone can help me if would be very helpfull hank you in advance

I used an 18 ga. staple to hold a vertical grain bamboo down. It got wet from not having the drain hooked up for the air conditioning condensation line and the kitchen floor got wet and swelled up pretty bad. The staples held and the flooring dried out and was still flat. The staples were an inch and a half long, into OSB. They sell the staples at big box stores.
You can also use 18 ga. cleats.
If you are installing strand bamboo then you should use cleats.