Not long, since both are very beginner friendly languages. I think I learned a good amount of python (not mastery but just becoming used to it) in about ~3 months or so, then javascript in a month. After you learn your first programming language learning others will get easier. Though this all depends on how fast you pick up concepts.

tl;dr It's different for everyone, but gets easier the more languages you learn.

As much as I would like to give you a specific timeframe, the hard truth is that it completely depends on the level of understanding that you want to achieve. If you're looking to learn syntax, it might take a month or two at max but learning programming itself takes years upon years. From personal experience, I would say to avoid looking at programming as something to learn in a timeframe but rather to take it up as a hobby. This answer is a bit short but if your looking for something more in-depth, I wrote a tutorial a while back on learning programming here

It takes a few months