They are two different words:
So here tu compañía means your company/companionship.
The accent matters:
Here, compañía means company in the sense of presence, companionship, or being with someone.
In Spanish, compañía can mean:
So in this sentence it means something like enjoying someone's presence while studying, not a corporation.
Because after cuando, Spanish often uses a normal conjugated verb to talk about something that happens regularly or generally.
Spanish does not always use the progressive form as much as English does.
So English might say when I’m studying Spanish, but Spanish very naturally says cuando estudio español.
You could say cuando estoy estudiando español, but that usually sounds more like a specific ongoing moment.
Por la tarde means in the afternoon or sometimes later in the day / in the evening, depending on context.
In Spain, the day is often divided like this:
So por la tarde is the normal expression for that part of the day. Spanish uses por, not en, in this common time expression.
Yes, Tu compañía me gusta is grammatically possible, but Me gusta tu compañía is more natural as a neutral sentence.
Spanish often places the indirect object pronoun first with gustar:
Putting tu compañía first gives it more emphasis or contrast:
So the original order is the most normal one.
The accent mark shows the stress pattern.
Compañía is pronounced with the stress on -ñí-:
Without the accent, Spanish pronunciation rules would suggest a different stress pattern. The written accent tells you exactly where the emphasis goes.
It also helps show that í-a is pronounced in separate syllables.
By itself, it most naturally suggests a habitual or general situation:
It sounds like something that happens regularly, not just once.
If you wanted a very specific one-time event, Spanish would usually add more context:
So the present tense here normally gives a general, habitual meaning.
Yes, but it changes the nuance.
Both are natural, but the original sentence sounds a little more elegant or affectionate because tu compañía highlights the companionship itself.