I can't remember what age I was, but I remember my mother writing letters to her brother in Australia, sending them off in first day covers, and seeing the pretty stamps on the replies.
I remember writing postcards and/or letters home from camps I went on with The Woodcraft Folk (I was an elfin, and later, a pioneer, but didn't venture onwards due to homework and other things). There was an international camp in Loughborough and the elfins went on a trip to a lemonade factory, while the pioneers went down a coal mine. Then, the following year, just before I started secondary school, I went to France with The Woodcraft Folk, and stayed with the group who'd stayed with us at the international camp. I wrote home.
Penpalling didn't start for me until 3rd year in secondary school. My German teacher was wunderbar. She organised a school exchange with a Gymnasium in Germany. I wanted to go, and those who also wanted to, were paired up with students from the Gymnasium beforehand so we could write letters (auf Deutsch). We had school trips both here and over there: Les Misérables was my favourite trip on this side, but over there, maybe Phantasialand! Weeeeee.
Sometime after the exchange, my French teacher passed round forms for the International Youth Service, for penpals. I ticked a few boxes and received letters. One was from Frédérick from near Toulouse, and another was from Singapore but I got her name wrong. I didn't know it was surname first, but then in public life, some people are referred to by their surnames (e.g. politicians). There were a couple of others, but with all of them, correspondence didn't last long as pressures of homework, and that...
I moved around for a bit, and that isn't exactly conducive to penpalling, but I did manage to keep up a correspondence with one penpal made through an advertisement I had put in newspapers around the world. Correspondence however slowed down for a while as other things in life have a habit of taking over. That correspondence lasted on and off for almost 25 years before he passed away.
Living in a somewhat rural area, not connected that well with big cities through public transport (no proper railway), and being an outsider here even after 20 years, it feels a lonely place. I have made some friends here and it is nice to see them for a chat, but that isn't always possible/convenient. OK, that may be just an excuse. But penpals are always there for when I write, it doesn't matter if they are asleep, or working, or having fun, or busy... Emails - I could send them but perhaps nowadays, these can be intruding on screen time of some sort or another, and maybe we need to get away from the computer (or other connected screen device). There is still a place for email. I have tried email correspondence but found it demanding - the email impatiently waits to be replied to. One person demanded almost immediate responses to daily emails.
However, I do also communicate with some penfriends outside of writing letters, be it through forums and discussion threads, or social media. Sometimes, a faster response is required, such as finding out how quickly letters are arriving, as events and circumstance can affect mail delivery (e.g. THAT Icelandic volcano a few years back halting most aviation in the more northern parts of the northern hemisphere, Covid, other natural events,...).
On that note, there is industrial action affecting Royal Mail. I'm on the side of the posties (could they end up on zero hour contracts, self-employed, earning less than current times...) but I do miss days without a delivery. There is quite a backlog of post (parcels prioritised over letters, but only Royal Mail have a monopoly for letter delivery), and there's warnings that Christmas Cards could arrive as late as February. I'm guessing that includes domestic, but hope my international post isn't that delayed - would Royal Mail like to pass on the international mail so it gets it out of their hands and away? However, they've brought forward the last recommended posting dates, with all the international ones passsed. They want us to allow almost 2 weeks for second class post to arrive, when it should take no more than 3 working days. I do have a couple of cards or so left to send overseas, so perhaps as wishing Merry Christmas & a Happy New Year, I should also wish them Happy Valentine's, Happy Birthday, Happy Unbirthday.... and ask them to apply as appropriate!