OK folks, for all of you answering, I can tell many of you don't know what an eSIM is, and are answering for old fashioned physical SIM cards. Please look up eSIMs as it is not the same thing. New high end phones support eSIMs where you download a virtual SIM rather than change physical SIM cards. Some phones like iPhone 14s and 15s sold in the USA don't even have physical SIM card slots any more and require you use eSIM.
you must not know what an eSIM is eSIM is not a physical SIM card New high end phones like iPhones now use eSIMs which are virtual software-based SIMs embedded into the device that do not use actual SIM cards. You download the information from the carrier to activate service rather than stick in a new SIM card. 7-11 definitely doesn't sell eSIMs.
Like every country, Thailand has different visa requirements depending on what passport you are using and how long you are staying. No one can tell you since you didn't mention your nationality. Please add that info.
Dianne gave a very thorough answer. Your best bet is to wait till you are 50 to do the exact same visa as your dad. During however many months you have until then, it is a simple matter of using existing options for American tourists (your residency in Mexico has no bearing as Thailand only cares about your passport country). USA passport holders can enter via visa exempt entry where you just show up without any visa and show your passport (30 days, extendable for 30 more days each time you enter), or with either a single entry or multiple entry tourist visa that you can very easily apply for from a Thai consulate like any tourist could. Single entry tourist visas allow one-time entry for 60 days, extendable one-time for 30 more days, giving you 90 days. You then go to a neighbouring country like Malaysia and come back in either via visa exempt (30+30 days) or on another tourist visa (60+30 days). Or, get a multiple-entry tourist visa, which gives you unlimited stays of 60 days each time, within the 6 month validity period of the visa, so you would need to leave the country once every 60 days, for example, to take a day trip to Singapore or Laos or anywhere you choose. By the time you do some combination of those options, you've made it to age 50 and can apply for what is commonly called a retirement visa. Keep in mind that entering by visa exempt entry (without having pre-applied for a single entry or multiple entry tourist visa) is limited to 2 land entries per year, and is technically unlimited for air entries, but Immigration may question too many repeated visa exempt entries and ask you to apply for an actual tourist visa. Doing it a couple of times is not going to be any issue.
just explain your personal situation and what you are trying to accomplish, and you might find that the answer is much simpler than you think
For example, say "I am a 70 year old retiree from the UK looking to move to Thailand permanently and I do not have a Thai wife" or "I am a 20 year old college student from Canada looking to stay in Thailand for 6 months" or "I am a 30 year old digital nomad from India looking to move to Thailand for a year while blogging" or "I am a 40 year old from Australia looking to spend 2 months going around different countries in Asia with multiple short repeated times in Thailand" etc. All of the above are daily scenarios that the members of this group deal with. You'll probably find your situation isn't unique and is common for members to advise you on. As someone else posted, it might be the difference between paying 1900 baht to do it yourself vs tens of thousands of baht or more to have an agent do the exact same thing for you that might take you 15 minutes to do yourself.
Isn't the issue with all those onward ticket sites that they don't generate a PAID ticket reservation with an e-ticket number? All they generate is an unpaid reservation that gives a PNR code but you could do that yourself by using any airline that offers a hold your price service for a few days.
Tod, you are the most important resource on the Thai visa groups for quality information. You're the Richard Barrow for visa advice. Thank you for your efforts!