QUES: Here the board bag is fold up inside itself and kept in place by means of some strips

correct the punctuation.

CORRECTED: Here the board bag is fold up "inside itself" and kept in place by means of some strips.

QUES: One of the primary roles of probiotics is promoting digestion

correct the punctuation.

CORRECTED: One of the primary roles of probiotics is promoting digestion.

QUES: Every year the European Environment Agency EEA compiles bathing water data gathered by local authorities at more than 22 000 sites across the 27 European Union Member States Croatia and Switzerland and measuring levels of bacteria from sewage and livestock

correct the punctuation.

CORRECTED:
Every year, the European Environment Agency (EEA) compiles bathing water data gathered by local authorities at more than 22 000 sites across the 27 European Union Member States, Croatia and Switzerland, and measuring levels of bacteria from sewage and livestock.