Using a save editor like
DaleKeeper might be the easiest choice. It is a single exe file, no installation. Just be carefull where you get it from to avoid any virus etc.
You can also use the cheat codes. First you need to edit the ini file to enable cheat codes.
[i]Cheat Codes
Note: The v1.05 patch is required to use these codes. This procedure involves editing a game file; create a backup copy of the file before proceeding. Use a text editor to edit the "
icewind.ini" file in the game directory. Add the line "
Cheats=1" under the
"[Game Options]" section.
Start the game and press
[Ctrl] + [Tab] to display the console window. Type "
CHEATERSDOPROSPER:EnableCheatKeys();" (case-sensitive) to enable cheat mode. Then, enter one of the following codes while playing the game to activate the corresponding cheat function:[/i]
Item names
Enter one of the following values with the
"CHEATERSDOPROSPER:CreateItem([item name]);" code:
The page doesn't show the code for bag of holding but you could try
BAG04 which is for Baldur's Gate.
References:
https://baldursgate.fandom.com/wiki/Bag_of_Holding https://www.cheatcc.com/pc/icewinddale.html EDIT: also found this post
https://www.gog.com/forum/icewind_dale_series/bag_of_holding_anyone_know_the_item_code