# How to predict individual customer spending for the following month?

I have around 140k transaction data of 35k unique customers that looks more or less like this:

ID     order_date     subtotal

000    2019/04/27     100
000    2019/06/03     200
001    2019/03/10     20
001    2019/03/13     50
111    2020/01/12     250
222    2019/12/20     75



There are other columns such as dob, gender, store location, membership_type, etc, but I think it's not that relevant to what I'm asking. I wanted to predict how much each customer will spend for next month only. Am I supposed to use ARIMA/SARIMA model or can I just use linear regression for this problem? If it's linear regression, what should be the label?

I'm sorry if this is a stupid question. I'm still very new to this field and I have only read about ARIMA model and never tried it before and always had the labels readily available for me when doing linear regression.