Three main struggles of immigrants:
1) Language barriers
Failure to communicate with Americans means less opportunities for employment and difficulty making new friends/contacts.
2) Cultural/race discrimination
Many immigrants wouldn't get hired for a job because of racism and cultural differences.
3) Financial issues
No work = no money = tough living situations.
If you want someone to write the whole essay for you, you'll have to offer a lot more than 15 points. But this should get you started. :)
