Ok, you need to read the component instructions as the best is at the end 
Basically you create 1 switch which is your broadlink device like this;
- platform: broadlink
host: 192.168.xxx.xxx
mac: xx:xx:xx:xx:xx:xx
Next you create a number of scripts, in your case 3 for each blind like this;
cover_1_pause:
alias: "Cover 1 pause"
sequence:
- service: switch.broadlink_send_packet_192_168_xxx_xxx
data:
packet:
- packet: packet_pushing_pause_button
cover_1_down:
alias: "Cover 1 down"
sequence:
- service: switch.broadlink_send_packet_192_168_xxx_xxx
data:
packet:
- packet: packet_pushing_down_button
cover_1_up:
alias: "Cover 1 up"
sequence:
- service: switch.broadlink_send_packet_192_168_xxx_xxx
data:
packet:
- packet_pushing_up_button
And you use these scripts in the template cover like this;
- platform: template
covers:
cover_1:
friendly_name: "Cover 1"
open_cover:
service: script.cover_1_up
close_cover:
service: script.cover_1_down
close_stop:
service: script.cover_1_pause
But you can do much more using script. For example my blinds are never in the top position, when I press up they go to a 75% open position. However when I open a window I call a script to put them 100% up which is not part of the template cover.