One-Touch dialin where to choose different locations?

The numbers between the + and the first , is the region phone number. You can change the available countries in the invitation by following https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0068094#h_01FA612NQ0HNCP3J3CT96WHAPN

Once you have a copy of the invitation you should have all the appropriate phone numbers.

Then you can copy one of the one click dial-in's and simply change the phone number. Remember that this link does not work directly for simple cellular phones that may/or may not receive email; however, even simple phones can be programmed to dial the string of characters from the phone directory or a one click button on the phone. This programming is helpful for anyone who is visually impaired. It usually requires someone to read the manual as each phone has a unique method for programming.