Exercise: I know how I (spend) the money my father (give) me last Christmas.

English as a Second Language English Vocabulary, Grammar and Idioms
1

Please help me with this exercise^^
I know how I (spend) the money my father (give) me last Christmas. I (keep) it until now in my Post Office Saving Account. I (just see) a beautiful watch in a jeweller’s shop. I (go) to the Post Office tomorrow, and when I (draw) out the money, I (buy) the watch. Come this weekend, I (show) you the watch.
Thanks !!!

2

I know how I (will spend) the money my father (gave) me last Christmas. I (have kept) it until now in my Post Office Saving Account. I (have seen) a beautiful watch in a jeweller’s shop. I (am going) to the Post Office tomorrow, and when I (draw) out the money, I (shall/will buy) the watch. Come this weekend, I (will show) you the watch.

3

thanks !
“I (am going) to the Post Office "
can i use " will” here ?

4

I will go to the Post Office is OK.ML.

5

Many thanks, Kitosdad !