Can only admins use the {{blocked}} template on talk pages? I know that only admins can block users, but can non-admins give them a notice that they’re blocked? Please help me with this.
No. Admins always put the blocked template on the talkpage. No need for you to do it to.
system
3
It’s not always placed on talk pages, especially when it’s a spambot (because they won’t really see it), but yes, it’s only meant for admins to use.