/u/horseshoe_crabby gave lots of great general advice! I would also add that the SPF suggests amounts of minutes of sun exposure before reapplying. So just something to keep in mind. If you investigate Asian brands (recs with links coming a little further down) then you also want to see if they have the highest PA of PA+++ or the newest level of PA++++.
Two American brands I can suggest are CeraVe sunscreen, which you can find at Amazon, drugstore.com, Ulta, CVS, and Walgreens. There's also another one that's minimal ingredients called Vanicream though it might be a little too moisturizing if you have oily skin. Or your skin could love it! You can find it at the usual places: Amazon, Walgreens, and drugstore.com.
However, if you feel like exploring there's lots of Asian options! Do some research and decide if you want physical or chemical (even if you stick with a Western brand) as they have different ingredients and protect you in different ways. There's also some combo sunscreens out there. Here's a mini summary about them here and some general sunscreen facts here.
Asian brands to rec: I like using the Innisfree sunscreens, which have an international shipping site. Though if you look around on other websites: roseroseshop, testerkorea, and Jolse you can find them there. They're also on Amazon BUT be careful of FAKES! /r/asianbeauty has a nice selection of Ebay and Amazon sellers.
Another Korea brand is Missha that has generally popular ones (particularly the pink bottle one). You can also find it on Amazon, Roseroseshop, testerkorea, and Jolse halfway down the page. You'll see that Testerkorea even has samples. If you look around on roseroseshop, testerkorea, and Ebay you can score samples so you don't need to purchase a full bottle if you want for some brands.
Biore is a very popular Japanese chemical sunscreen you can find on Amazon, Ebay, or a website called SaSa. Japanese sunscreens do tend to have alcohol in them though, but that might not bother your face. It's associated with being a super speedy absorb-er so there's minimal wait time before putting on your make up and little issue for reapplying.
Shiseido Senka is another popular Japanese sunscreen others try as well. You can find also on Amazon, Ebay, or Sasa I believe.
Hope this helps!