okay, wcs_givelevel is not a client command.. this means you have to use it with rcon.
and actually, you can't use it with name, only with steamid
he has right go console type status and u get the player nuber so u type in the console rcon wcs_givelevel 13 (player number ) 1000000 (lvl)
Now for the list off all the "wcs_" console commands and their syntax!
* wcs_addonreload <NAME>
* wcs_givecredits <userid> <amount> <reason> <forced>
* wcs_menuzero <userid>
* wcs_flash <userid> <targetid>
* wcs_showcredits <userid>
* wcs_removefx <userid> <effectype>
* wcs_setfx <userid> <effectype> [<time>]
* wcs_giveitem <userid> <item>
* wcs_explode <userid> <targetid> <magnitude> <radius>
* wcs_dealdamage <userid> <targetid> <magnitude> <radius>
* wcs_saveplayer <userid> <full>
* wcs_getplayer <userid> <full>
* wcs_checkevents <userid> <type>
* wcs_showinfohandle <type>
* wcs_notice <userid> <text>
* wcs_debuglog <text>
* wcs_restrict_purge <userid>
* wcs_restrict <userid> restrict <weapon>
* wcs_restrict <userid> allow <weapon> <give> <knife>
* wcs_restrict <userid> addallow <weapon>
* wcs_restrict <userid> knife
* wcs_restrict <userid> knifeonly
* wcs_givexp <userid> <amount> <reason> <forced> * wcs_givelevel <userid> <amount> <reason> <forced> * wcs_showxp <userid>
* wcs_deathhandle <userid> <attackerid> <weapon> <headshot>
* wcs_getlanguage <var> <id>
* wcs_race_menu <userid>
* wcs_showraceinfo <userid>
* wcs_shopmenu <userid>
* wcs_giveshopitem <userid> <itemid>
* wcs_showshopinfo <userid>
* wcs_deathhandle_items <userid>
* wcs_showtop10 <userid>
* wcs_checktop10 <userid>
* wcs_cleartop10
* wcs_mole_activate <userid>
* wcs_regeneration <userid> <amount> <time> <maxHP> <maxHeal> <radius>
* wcs_warden <userid> <duration> <damage> <radius> <target team> <team target name> <x> <y> <z> <round>
* wcs_spendskills <userid>
* wcs_showplayerinfo <userid>
* wcs_showskills <userid>
* wcs_resetskills <userid