Real Buddhists are likely the most expert meditators you can find. And meditation, like anything worth doing, benefits from good teaching. Buddhism is not an evangelical religion. Thus a real Buddhist teacher will be happy to teach you meditation without requiring you to "profess your faith" or any of that silly nonsense.
This is a gift. Not only can meditation be a "separate thing", but those who are the most expert will be happy to unpack it from their own beliefs and teach it to you as separately as you like, because of those beliefs.
Isn't that beautiful? Does it remind you of open source at all?
(Also - if you decide to go further with this, you might make up your mind whether there is some reason Buddhism and mind training correlate so highly, beyond history.)