Long story short: I’m (24M) American, and I’m visiting my long-distance Romanian boyfriend for the first time soon. In Romania, most cars are manual - including all the ones owned by my boyfriend’s family (I’ll be staying with them). I’ve never driven a manual before. His dad told me he can give me a quick lesson, and that I’m welcome to use their cars if I want; otherwise, I can rent an automatic. I don’t have access to any manual cars here in the U.S. to practice on, so I’m not sure what to do.
Driving manual is not particularly complicated, but it will require you to focus a lot of attention on it at first. Since you also have to cope with with differences in driving regulations, this will put you and your passengers more at risk than necessary.
It takes time (~tens of hours) to build the muscle memory so that it becomes natural. For a vacation in the short term, you should go ahead with your plan to rent an automatic.