Formulas missing in Pages table on iPad 10th generation

Since I became disabled and spend lots of time in bed, I now use my iPad for just about everything! Now I am learning Apple products and I,am trying to do some of the things that I used to do in the world of Word and Excel.

So, I have made a bunch of simple tables in Pages. Each one only has two columns. For example, Column A lists out where our money goes: utilities, food, direct debits etc. Column B shows how much money goes to the companies in Column A each month. Seems pretty simple!

All I want to do is get Column B to show me the total spends at the bottom of the column. I have been searching around for hours this morning and cannot see how to do this. I have seen videos telling me to find a formulas menu, but I can’t find anything like that. Am I just being stupid?

My iPad is 10th generation, IPadIOS version 18.3.

Thanks for your help.

[Re-Titled by Moderator]