Translation:It is over here.
Literally one means "here" while the other means something like "this way" or "this side", but the reason こちら is used in this case is because it's more polite.
As an aside, in a different context こちらです could also translate as "it is me", "it is us", or "it our <side/party/group>" (specifically excluding the listener in each case), whereas そちら can mean "your <side/party/group>". These are also considered more polite than, say わたし. For example, when announcing yourself on the phone instead of using わたし it is better to say something like こちらはDuolingoユーザーのJadeです
ここ is the location of the speaker, while こちら is the direction towards the speaker. こちら could be better translated as "this way"
こちら seems it can be a more polite way to say "here" as well. Often I would just say this mean "This way" (towards the speaker)
"It is this way." is a more accurate translation. I associate こちら with a direction rather than location. Like if you're in a maze and you're stuck at an intersection, it would make more sense to ask "Which way is the exit" or 出口はどちらですか？ rather than "Where is the exit?" because you're asking about the process of getting there rather than the end destination itself.