Hi @Adarsh 

IFS provides a migration tool for performing the data migration work. Here you can create migration jobs for loading the data from excel (csv) into temporary tables and from there into the IFS tables. It also supports to decide wether when migrating the data the record does exist (means update must be performed) or the record does not exist (insert must be performed).
When you say script I guess you means writing your own pl/sql developer scripts? Here you have to program everything by yourself, e.g. differing between insert and modify call, exception handing and so on.
I would suggest to work with the migration tool. 
Also I guess in IFS Cloud use of scripts is limited. 
If you are not familiar with the migration tool it could be an option to book an training for this tool.
Would also be interesting to know which IFS version you are using.

Best regards