The prefix pri-, when used with verbs of movement, means a direction reaching something or towards something.

prieiti - to reach something by walking, to walk towards something
pribėgti - to reach something by running, to run towards something
privažiuoti - to reach something by driving, to drive towards something
priskristi - to reach something by flying, to fly towards something
prijoti - to reach something by riding, to ride towards something
priplaukti - to reach something by swimming, to swim towards something

Aš prieinu mokyklą. I reach the school (by walking).
Aš prieinu prie mokyklos. I reach the school (by walking).
Brolis pribėga namus. Brother reaches home (by running).
Brolis pribėga prie namų. Brother reaches home (by running).
Laivas priplaukia miestą. The ship reaches the city (by swimming).
Laivas priplaukia prie miesto. The ship reaches the city (by swimming).
Arkliai prijoja kaimą. The horses reach the town (by riding).
Arkliai prijoja prie kaimo. The horses reach the town (by riding).
Paukštis priskrenda Latviją. The birds reach Latvia (by flying).
Paukštis priskrenda prie Latvijos. The birds reach Latvia (by flying).
Greitas autobusas privažiuoja stotelę. A fast bus reaches the bus-stop (by driving).
Greitas autobusas privažiuoja prie stotelės. A fast bus reaches the bus-stop (by driving).