You can practice your specific weapon skills by play some small map build for specific weapon
1. Map name : awp_map_fair to improve your sniping skills. Try only using the sniper in this
game and 1 more thing usually u are not allowed to add a bot in this map that means you need a friend to continue. But hey you can try other map like de_aztec but as i stated earlier that only use sniper.
2. Map : cs_untitled2 , this map is small and quiet a fun. You can practice pistols and guns(any)
and same as the earlier map that you can't add a bot. So can go for any big strategic map like de_dust2, de_dust. This will add on to your inner clan communication and strategy.