How to measure high ampere with a Multimeter.

Hello people,

just yesterday i found out through my own discovery that my Multimeter has 2 fuses and both seem to be broken, because it doesnt sho Current anymore. I tried to look up how to measure current and was told in a tutorial that you measure current not across, but through something. I dont really know what to make with that and how to understand that.

A few weeks ago i was trying to repair an electroroller and started to "check the battery"..i switched the probe in the 10 amp socket, put the probes on the battery and caused an impressive shortage. The battery was 12 amps and 48V as i found out later. Well it was above the amp fuse, but later somebody told me thats in general the wrong way to measure current and that you never to that, even if it was less than 10 amps. Well if thats true, than i cant even measure a 16340 battery on current? How else am i supposed to do that? Do you have to wire a resistor to the battery and then measure and make some calculations?

Help would be appriciated.