>>785600Open Water PADI here
You can do this in about a week. all of the course material is done online ( you can do it in the hotel or wherever you're staying over an evening meal) and you do maybe 7 or 8 dives
I would get certified before thinking hoo-ha! and going diving. you learn shit that keeps you alive. if you don't learn how to control your bouncy you you're like a drunk cow trying to get around under water, if you don't learn to do certain things, like observe bottom time, surface intervals the way different gasses expand and diffuse in your tissues at pressure and how to read a dive table, or when you come up you'll get get the bends and end up in a hyperbaric chamber if there is one there, if you don't learn how to communicate you can end up lost, or intercommunicating a dangerous situation, if you don't learn you to check your gear and other's gear before a dive you can end up in a world of shit ( I've seen people miss putting o rings on at 1st stage and all kinds of shit at 'resort divers' ) you have to learn how to safely ascend without rupturing a lung... the list of shit that can go wrong is endless and unless you have gills, no matter how shallow you think the water you're in is, it's a fuckin' long way up when you start panicking
it's not just a jolly with the fish, shit like this is genuinely dangerous which is why training courses and certification exists. If a resort is offering sketchy 'try dives' I'd be wary as fuck. I'd want to see their dice leader's diver certification number (with PADI you can check it all online, and it even gives photo ID so you can see if they are actually qualified for this shit, or just someone that knows how to dive )