Hi. Welcome to GMAT Club.
1. Once you take the test, your score will be provided within about 3 days. At that point, no action from you is needed to preserver it.
2. However, you do get 5 free score reports that you can send out if you do that within 3 days of receiving your official score (not within 3 days of taking the test but receiving the score). You can send the scores up to 5 schools for free. Otherwise, if you do this LATER, it will be $35 per school - pricey!
You should definitely send the scores if you are happy with them. They should have access to them for up to 5 years. There is no harm in sending really unless these are LOW scores or borderline. In that case, you may as well hang back and worst case, you will have to spend $35 in a few years.