Most modern eBicycle have a swappable battery. For extra convenience aim for big brands like Bosch or Shimano but other brands are not a huge deal to swap as the voltages are mostly the same: 24, 36, 48. You sometimes need to keep the BMS + connectors part but that’s not a big deal either with a few screwdrivers.

Don’t buy non-removable batteries bikes without the advice of a mechanist but those bike are not the norm.