How to study: Start by actually doing it. I see people spend more time on study planning than on actually learning. Others spend hours trying to determine what will or won't be tested rather than just learning the material. See Arnold Rimmer.
How do you actually get yourself to do it? What are the blockers, and how does one deal with them?
Retired now, but his has helped me for all 40+ years of my programming & business careers.
Sometimes, the lack of drive is because it's not something you really want to do.
Caveat: while not super common, in my case the "not having the drive despite being x/y/z good traits" just turned out to be undiagnosed ADHD. Dopamine is strongly linked with willingness to do tasks and is affected in ADHD. Of course this isn't the case for everybody, but if you/someone is chronically late/procrastinates, is very unorganized/messy, struggles to finish tasks etc - it's worth googling executive dysfunction at the very least, and then perhaps talking with your doctor.
For instance, remove all the bad food from sight and replace with good ones. Put on shoes and active wear before even deciding to do some exercise. And many many other tricks..
There's nothing wrong with a little bit of "learning to learn," but you have to be on guard against using it to do the hard work.
with respect to those particular questions:
many more people speak spanish than italian due to colonial-age history, and portuguese is almost a spanish dialect. for us residents with culinary aspirations, it may be worthwhile to know that spanish is required for most us restaurant kitchens. but italian isn't that far from spanish either; learning either spanish or italian will make it much easier to learn the other
ancient greek or biblical hebrew depends on which books you want to read. the torah is in biblical hebrew; platon, the hellenistic scientists, and the new testament are in classical to koine greek. modern hebrew will help you a lot with biblical hebrew, because it sort of skipped 1800 years of the sort of linguistic mutation that transformed classical latin into spanish and italian, and it is of course mandatory for living in israel. it may be helpful for flirting with israeli backpackers too
--Cassandra Wong (Tia Carrere), Wayne's World, on how she learned English