@LoyceV Thank you.

Some parts of the process, mainly how to send BTC from Electrum to Ledger I'm clear on. Others, a little less so, all this about claiming BCH and BSV (and potentially others you mention), but I'll figure it out. Like you said, I'll do the most important thing first, which is secure my BTC by transferring it from Electrum to my Ledger. Although, because of the super-high fees, I've put this off for now too, and am trying to figure out the best way forward. Are the fees likely to go down at any point? Is it even possible to know this?

Again, thank you all who have contributed here, you've really helped me out, really appreciate it!