Use yr hand and finger as indications.
Pointing someone(real human) with yr finger( index finger) or chopsticks is one of bad manner, though.https://gurunavi.com/en/japanfoodie/2015/10/chopstick.html
Counter words may a bit hard to remember all perfectly.https://en.wikipedia.org/wiki/Japanese_counter_word
For the food that stuck(or wound) on the stick is "1本,,," using best,
but actually we do not mind even with "1つ,,," or "1個,,,", this is not wrong.
1個,,, sounds like a kid than 1つ,,,. (no bad meaning just like younger/teens, pretty frank)
The order of coffee is a bit different depending on the convenience store,
basically it is payment at cash register first, using "coffee maker(machine)" is self-service.
For "ice coffee" brings cups with ice to the cash register from the refrigerator first.
However, fr last Nov new coffee maker with coin insert slot has started.(only for Regular size) https://www.instagram.com/p/BUYWL93DC2E/
But it has not yet spread nationwide. (no sure by machine price or other reasons?)
こちら/こっち(for me) then こちら(for yr friend, family or group) is better.
1つは私(に)、もう1つは、彼/彼女(息子/娘)に is the best.
Using そちら when closing is not good as Honorific. (sounds like unknown or bad relations)
When indication a remote place as out of reach,
"そちら/そっち" or "あちら/あっち" possible as "over there(むこう/向こう)".
(こっち/そっち/あっち are not Honorific)
Basically, "honorific words" mainly "お" or "ご" are not used for myself,
but honorific expression exists as an exception as custom.
If these can be understood perfectly, you may pass the "N1".