Hi!
First: Get the text
Run a Get-Text Activity (choose the part of text needed) and assign the content to any variable you want.
Second: Split the text
Split the text by using the String variable from step1 and assigning its results to a new array variable like this:
…
StringArrayStep2 = StringVariableStep1.split(","c)
…
Third: Geht the ID
Step 2 will give you an array and you can access the ID like
…
ID=StringArrayStep2(0)
…
That should solve your issue and once you get used to it you can put these steps together into one, but thats advanced.
However, UiPath already offers a Split Text activity you can use as well: