Can we obtain pure water from pond or muddy water by filtrationexplain?

It depends on what type of filtration method is being used. Particle filters can be used to strain undissolved material from the water resulting in clear water. But it may not be pure since it will not remove chemicals dissolved in the water.

If you know what impurities are in the water, it may be possible to treat the water with chemicals to nullify or precipitate the impurities. But it still may not be pure as the resulting chemical reaction may leave something else in the water.

The best way to actually get pure water is to distill the water. This is done by boiling the water to convert it to steam and then cooling it to convert it back to water. Chemicals in the water will either be left behind in the original container or boil away as gas and the resulting steam will condense as pure water