Can someone let me know the easiest way to call the US? I need to get in touch with my bank and I think it’s a toll free number, but my phone won’t let me dial internationally

At home (Canada), I use an app called textme - my cottage has poor cell coverage but I have wifi. So I call forward my cell# to my textme# and that way I receive all my calls over wifi. This would be great to use in Thailand, but I have a feeling it won't work there? Or are there other similar calling apps that work in Thailand? Or would I need a VPN?

For past trips I subscribed to Skype's unlimited calling ($3 per month) which is great for making calls to landlines, but for people calling me, I end up just calling up my voicemail periodically to see if I have any messages since there is no way to get notifications. It would be awesome if my calls just rang through to a web-based calling app like textme.

TIA

Am I correct that to use this app one has to order the $4.99 SIM card that comes in the mail in order to get an American number to enjoy unlimited calling from Thailand 🇹🇭 to the United States 🇺🇸 ???