Don't DIY this. You'll waste so much money. If the AC system is empty, then there is no other possibility outside of a leak being the cause of that. Something's busted. Since that's the case, you need to find the leak and repair it before dumping $$$$$$$$$ in refrigerants.

If you overcharge the system, you will destroy it. If you use the wrong refrigerant, you will foul the valves in it. If you charge the high pressure fitting instead of the low pressure fitting, the can of refrigerant you're trying to add to it will explode and possibly injure you.

Can you do it yourself? Yes. But you can't charge an empty or self-serviced AC system PROPERLY if you do it yourself because you won't be able to afford the equipment that does it right. Before adding refigerant to an empty AC system, you have to suck all the air out of it or else it won't work right. DIY charge kits don't create any vacuum. In order to correct the problem caused by this, you would have to take it to a garage and have them do an AC service, and still pay the same price for it despite having already filled it. You can repair the AC yourself, but don't charge it. Take it somewhere for an "evacuate and recharge". Most shops will do a R-134a charge for under $90, it works 5x better without air in it, and there are tons of Honda AC systems in junkyards if you need a part.

So why do they sell DIY AC kits? Because there's a sucker born every minute that will pay top dollar to do the job wrong. Either that or there's a few cars that have been in accidents and they didn't leak ALL the refrigerant out... or cars that were manufactured with the AC system barely charged. May mfr's do this because it saves them a shit-ton of money to skimp on a half pound of refrigerant on every car they build. The remaining pound or two will get the job done, right? These DIY kits only work on AC systems that have LOW pressure.