Is there a cheat code to get visa points?

No cheats. But one of the mods (which I don't use) does increase visa level. (Don't ask me which mod it is though. I have no idea. I've just seen people here talk about it.)

There are ways of getting your visa level up quickly using adventures. The way to double the points is to have the Opportunistic Lifetime Reward. That way you get the number of points needed for a visa level more quickly. I've never used it, but the Adventurer goal is supposed to get there more quickly too.

You don't need mods for this so no downloading :)

It looks like alot of text but this does work for me and it should work for you too.

you do need cheats though so on the main menu, bring up the cheat box (CTRL+SHIFT+C) and type in "testingcheatsenabled true" and "buydebug"
When you go on your vacation, you can go to the lifetime rewards and click between the amount of points and the treasure chest icon to get more. Keep clicking until you can buy oppurtunitistic (or hoever it's spelt) and that will give you visa points much faster than normal when doing tasks for people.
Then when you're in tombs you can drag your sims needs up so they will never get hungry or sleepy and it will make those adventure much faster so it won't be as annoying to do them.
You can also hold CTRL and SHIFT and click on the ground to but on that lot. then go to "funtion" then you will find buydbug where you can get items that are usually locked that will help with your adventure.

I don't know how to skip all of this but this way is quiker than it looks!

I know how to get instant visa level! Download Nraas DebugEnabler Mod. Then go into the game and make the sim you want the visa level for your active sim. Click the sim, click nraas then click the smartphone option. The click add/set visa level. And then type in 0 to 3 for whatever visa level you want!

@Sammi_J , the Op asked this question more than 10 years ago. It's very likely that they have figured it out in the meantime. I know you didn't do it on purpose, but this is against the forum rules:

https://forums.thesims.com/en_US/discussion/983366/lets-talk-about-necroposting-%F0%9F%A7%9F#latest