sims 3

@kirstey08  Your laptop is actually under the minimum requirements for the 64-bit version of Sims 3, and your operating system won't run the 32-bit version.  (By the way, you should update your OS: the newest version of Catalina is 10.15.7.  I'm not suggesting you install Big Sur or Monterey, just update Catalina.)  This doesn't mean you won't be able to run the 64-bit version, and in fact I've seen reports from a number of players that the  base game and some packs run just fine on exactly the same hardware as your laptop has.

However, I would absolutely not recommend installing Pets.  A few players on your Mac have been able to get the game to stop crashing with Pets installed by disabling Advanced Rendering; others have needed to uninstall the pack entirely.  So unless you're comfortable taking that risk with your money, or you really badly want pets in the game (or it wouldn't be a waste because you'll buy a new computer and use the pack at some later date), it's best to skip the expansion.

The other packs are mostly fine with the exception of Late Night, more specifically playing in Bridgeport.  But here, reports are more spotty, and you can certainly use the features of LN in other worlds.  The same is true for the world of Isla Paradiso, on any system.  Seasons is the next most demanding pack after Pets, but there aren't any game-breaking issues, just lower performance overall.

Given that your laptop isn't that powerful to begin with, I'd suggest buying the starter pack, which comes with Late Night and a stuff pack, and perhaps one or two other early expansions (World Adventures, Ambitions, or Generations) if they interest you.   See how the game runs on your laptop, and if you're satisfied, start adding the other expansions you want one at a time.  If performance starts to suffer, stop there.  Stuff packs won't have a meaningful impact; it's only the later expansions that make the game more demanding.

@puzzlezaddict 

Thank you. I know there are 32 bit and 64 bit for sims 3.( two version)

When I first buy the base game, which version will I get ? Will I get 64 bit version or the 32 bit version? 

It is important as my laptop cannot run the 32 bit sims 3.

@kirstey08  When you buy a copy of Sims 3, you're buying the right to run all the versions.  So you should see both the 32-bit and 64-bit versions in your game library.

Sometimes the "entitlements," as they're called, for the 64-bit versions of the base game and any packs don't get applied to the account, but this is a mistake on the EA side and can be fixed by contacting support.

@puzzlezaddict 

Thank you for your reply.

I have checked the price in steam and origin. I found out there is a discount in steam recently. 
but I am not sure whether steam has 64 bit  Sims 3 version or not. 

Does steam has 64 bit version ? Or do I have to purchase sims 3 in origin? 

thanks 

@kirstey08  The Steam version of Sims 3 only runs in Windows.  What you could do, if you have at least temporary access to a Windows computer where you can install Steam, is buy the game in Steam, then take the CD keys Steam provides and register them in Origin.  (The CD keys are not viewable in macOS.)  The game will then show up in your Origin library just as if you'd bought it from there directly.

@puzzlezaddict 

thanks.I will update my laptop into Catalina 10.15.7 version before the purchase . But I want to ask can Mac OS Monterey open sims 3 too ? 

Just in case I want to update my computer system in the future.

@kirstey08  Yes, Sims 3 runs well enough in Monterey.  However, I'd stick with Catalina, at least for now: the Monterey graphics drivers are having issues handling Sims 4, and the OS itself is more demanding.  So updating may just add another issue or two to the situation.