The name is bicyclo[3.3.1]nonane.
Here's how to determine the name.
1. Count the total number of carbon atoms (9). The base name is nonane.
2. Determine the number of rings.
The number of rings equals the number of cuts you can make in the molecule without having it fall into two pieces.
You can make two cuts, so the name becomes bicyclononane.
3. Identify the bridgehead carbons.
(Adapted from NIST/TRC Web Thermo Tables (WTT) - National Institute of Standards)
They are marked by asterisks above.
4. Count the number of carbons in each bridge between the bridgehead
carbons (3, 3, and 1).
5. Arrange the numbers in decreasing order with periods between them (3.3.1).
6. Insert these numbers in brackets just after the bicyclo part of the name.
The name becomes bicyclo[3.3.1]nonane.
Your structures represent two different conformations of the same compound.
The first structure is called the chair-chair conformation, and the second is the boat-chair conformation.