Q.how and when to plant mugo pine shrubs
can the mugo plant shrub be planted in a pot

Look for dwarf varieties of Mugo Pine for best results in containers.
Pots should be about as wide as they are high for best insulation of the roots. Clay pots are heavier than plastic but are more stable in windy conditions.
Instead, use a soil-based compost, with good organic matter content and preferably some perlite or pumice to make the mix porous, which keeps air in the soil.
https://www.gardeningknowhow.com/ornamental/trees/pine/mugo-pine-information.htm