Buy a simple tracker with a text Protocol, such as Sinotrack ST-901
or - GT06
(the links are not for sale, just a description), set the SMS commands to your server, take data (Yes, the socket server), stored in a database and all of that.
These models are in any case not a direct recommendation, just for some reason they are popular right now.
About "every few seconds" - this is a more advanced models.
Here is a list of over 600 models of GPS trackers
and each has the possibility of migration to your server.
Simple models typically transmit data once in 10-30 seconds.
If you order is not in Russia, it is still recommend to read: https://habr.com/post/413449
. Just in case, suddenly do not know.