All the servers I have come across have been for players of all skills. It's just one of those things that people accept while playing and rarely causes any upset.
The best advice I can offer is to perhaps start with deathmatches or team deathmatches. Try to avoid servers with too many people playing though, especially for regular deathmatches as it becomes too chaotic to be enjoyable. It can become a challenge in itself to just survive for 15 seconds.
For deathmatches I usually play on servers with no more than 12 people, and for team deathmatches, no more than 20 people.
One you've become familiar with the maps and improved your rank, you may want to look at Search and Destroy matches. They are much more involved but once you die, you have to wait until the next round to respawn.