SIM Activation and Use

[Xul]

if I can not download app on my phone can I still use the SIM card for that phone?

[Meow]

You have to use PM app in order to activate SIM/account.
Do as @softech suggested but do NOT buy eSIM as it is not transferrable! Get physical SIM even if you have to wait a little bit for it to arrive.

[softech]

@Xul 

you can ask a friend to download the app on his/her phone, run through the activation for you on his/her phone.  Once the activation is done, you can then insert the PM sim card in your phone