There are lot of different saving options for N64 emulators, it comes down to your preference and what works.
.j.
No a N64 keyboard does not exist. You can play N64 games online using an emulator which you then use a keyboard to control, but there is no attachment keyboard for the N64 system. .j.
There are 387 published games for the N64. Some of the games were country exclusive.
Yes
Yes the n64 can but to play Japanese games on the system is to get rid of the plastic tabs in the cart slot because that stop Japanese games from going in.
swapmeets
Yes Goeman games work on the N64 for American Systems. To make sure you have the correct cartridge, look on the back of games for NAL - this means North American and will work for your N64. However PAL and JPN will not work unless you have that specific game system.
it has about 380 games
Nope.
yes
No.
It's the same one you use for the Banjo games
You can do a search for "n64 online" & find some game that are very similar to those Nintendo games. However, to play those game you will need to download an N64 Emulator graphics plugin for it to work properly.