Fair points Agustin & shingwell.
For the record though shingwell, I'm not the time served EE & successful businessman I referred to, Mr Eric Gibbs is and offered a possible solution from a pound shop, only to be met with "I know I could build something, but could use a few for various projects and am just being
lazy!"
There are many posts made to this and other forums, where the OP:
Provides scant information in relation to the project as a whole, which then has to be teased out in further posts, in order to offer a viable solution....
Makes posts looking for components which are already easily found by doing a Google search..... or
Expects others to do their research and sit back and do nothing - "lazy" ;-)
Now we know a little more about what you actually intend to build, links to inexpensive solutions can be offered, which could also be modified to suit other future projects.
I did a quick search for your required application and picked out the following from many hits:
**broken link removed** (The sounder pitch can be adjusted for different projects)
http://www.hobby-circuits.com/circuits/automotive/automotive-light/693/simple-headlight-reminders (This one has two versions. Continuous or burst)
And a third from these forums:
https://www.electro-tech-online.com/threads/headlight-on-warning-buzzer.115498/ (Uses a 12V buzzer + diode if req'd)
Regards.
EDIT:
If a piezo buzzer is too loud, you can always modify the aperture or wrap it in foam to quieten it somewhat.