The thing you are looking for is HLTV, which is something that has been around since goldsrc under sv_hltv: https://developer.valvesoftware.com/wiki/Console_Command_Lis...

I haven't looked at the config/set one up since HL1 days so here is a relevant article to how you would set that up https://support.steampowered.com/kb_article.php?ref=1990-UAV... and I am sure there is an equivalent one for source/hl2 games. It lets you set things like delay and so on and I remember it being relatively straightforward.