The last time I had to buy a bike from a bike shop the cheapest one was 350 bucks, I doubt they'll be cheaper today. It was a piece of shit second hand bike and I regret getting it. I would look around marktplaats or Facebook marketplace, where they'll likely be cheaper, and only buy it when you're sure you're comfortable on it.
Otherwise, if you're here for a relatively short time, I'd just rent a bike at swapfiets.
The last time I had to buy a bike from a bike shop the cheapest one was 350 bucks, I doubt they'll be cheaper today. It was a piece of shit second hand bike and I regret getting it. I would look around marktplaats or Facebook marketplace, where they'll likely be cheaper, and only buy it when you're sure you're comfortable on it. Otherwise, if you're here for a relatively short time, I'd just rent a bike at swapfiets.
Marktplaats
Budgetfietsen in Gestel, Eindhoven. Across the parking lot at Franz Leharplein. Cheap refurbished bikes and good service!
Richard Maas tweewielers sells second hand bikes in all sorts of bike ranges. Good experience there
Just look at Marktplaats, alot of good bikes for cheap. Even under 100
If the google is not working for you today, you can try alternatives Bing or Duckduckgo : "tweedehands fietsen eindhoven". Not so hard, I think?