How I can difference the translation of 'om' because it has a lot of meanings and I confuse them when I read.

See a translation

I think it makes sense to default to the "if" meaning, and if that doesn't make sense, focus on the basic meaning: around, about, alrededor de, sobre (usually fully wrapping or in a circlular motion, like a reel), since basically all of the other meanings are related to this. Similar abstractions exist with those English and Spanish words too.

When talking about time, you have two basic forms:

1. jag äter två äpplen om dagen = cada dia como dos manzanas
2. jag kommer äta två äpplen om en dag = después de un día voy a comer dos manzanas

In 1 the time is in definite form (dagen), in 2 it is not (en dag).

With both time and space, you can think that you are "wrapping" it. E.g.

1. till höger om vägen står ett barn och väntar på bilarna = al derecho de la calle hay un niño esperando los carros
2. bilen kör på höger sida av vägen = el carro va por el lado derecho de la calle (pero sí por la calle)
3. bilen kör om cykeln = el carro adelanta la bicicleta

If "om" comes directly after a verb it is probably part of a phrasal verb, meaning something like "re-" or "around". These ones I think you unfortunately need to learn one by one.

Sorry if I made things even more confusing! 😅