I found this on the beach what could it br

It's an ampoule with probably some kind of pharmaceutical substance inside. Looks a lot like Iodine color-wise (example), but could be something else.

Be careful a glass like that could have anything in it from a stink bomb to a vitamin supplement or something corrosive that could burn your skin or poison you.

What does it taste like?

That's an ampule. A chemist created it by putting a chemical in a glass test tube, then heating it with a torch to melt the glass and seal the chemical inside. When you need the chemical, you break the glass. It looks like this chemist used a clamp to make breaking the tip off of the ampule easier, implying the chemical is meant to be poured out.

The ampule could contain anything. The most common chemical to come in such an ampule is iodine, but it's much more common for iodine to be packaged in something else nowadays.

The second most common chemical in ampule is stink bombs, but those are usually much smaller and the tip isn't clamped because the ampule is meant to be be thrown and shattered to release its contents.

tl;dr It's most likely full of harmless disinfectant, but you shouldn't count on it. Give it to professionals who can safely identify it and dispose of it if needed.

Sorry for bad english

my granma used to have these, i think it's iodine. you'd break the vial and use the liquid to disinfect smaller wounds

That is how stink bombs looked when I was a little kid. The liquid was lighter, but exposure to elements could cause a change.

You buy them at the same stores that would sell fake cigarettes that puff or hand buzzers. You are supposed to throw it or drop it and crunch it with your shoe to release a terrible (but temporary) odor. Example

We still get medicine with that kind of packaging (EU)

I had vitamin D supplements like this

If it's dark brown - almost red - could be iron for injection.

Looks like a vape cartridge of some kind.

Are their Asian food joints near by? Looks kinda like some soy sauce.