In general unless its a sealed type with no obvious caps yes.
Clean off the battery terminals for the charger and remove any dirt or grease from the cell cap areas, gently unscrew them and carefully lift them away, place an old clean dry rag or similar over the open ports and tap the battery to release any trapped gas, then when you are sure its safe, check inside for your fluid level and if required top up with deionised water.
gently place the cell caps back on top without screwing them hard down and connect your charger to the terminals, red for positive / black for negative, and only then plug it in and switch it on at the power source,
Once charging is complete make sure you switch the charger off at the power source and unplug it before removing the connectors from the battery terminals.
Get it back to front and you could explode the hydrogen gas that the battery is giving off, showering you in acid and shrapnell.
Finally let the battery settle for a while before you move it, run through the tap check as before to expell excess gas remembering to cover over the cell ports to avoid splashes ensure the cell caps are back in and snug and again use a dry clean old rag or similar to lay over the cell ports as you carry it just in case there may still be any remaining trapped gas which could surge and spray you with acid.