I bought this Vastar Watch Repair Kit, Watch... https://www.amazon.com/dp/B07H8D23L6?ref=ppx_pop_mob_ap_share
Amazon sells watch kits, they come with a little hammer and/or screwdrivers. Or you can get them from Ali if you don't mind the wait.
https://www.amazon.com/dp/B07H8D23L6
I have something like this which pretty much comes with everything I'll need.
Is it because the head of your screwdriver too fat? You need something small at around 1.4mm head. Either get one for cheap on Amazon for $5-8 or get this tool set that come with 3 screwdrivers and other items that may be useful in the future.
Get this: Watch repair kit on Amazon
I would recommend getting a kit. I use it more than expected. I grabbed this one off Amazon and it works just fine.