How to replace characters in my logs so they can be filterable

Hello,

I have logs that are writen like this:

43790,2021-01-31,22:32:24,57,21

As you can see, this is not very filterable for grafana (its like this because we read these logs through excel),I need them to look more like this with as little effor as possible:

A=43790 B=2021-01-31,22:32:24 C=57 D=21
Does anyone know a program or way how to do this?
Thank you for your answers.

With best regards,
Oto Weinlich