During the or EoR (400 Myr to 1 Gyr after the beginning of the universe) matter stopped being neutral. The causes and origin of this phenomenon are not yet fully understood. New information of galaxies in the EoR such as their physical properties, age of stellar population and emission fraction of ionizing photons will allow us to further deepen our knowledge of this objects. GO1 JWST approved proposal #1840 (Álvarez-Márquez+21) will shed light on the epoch of reionization by means of studying a sample of high redshift, [OIII] 88 μm emitting galaxies previously detected with radio interferometer ALMA (Atacama Large Millimetric Array) in order to understand how their light can ionise atoms. In this work we study whether structure of stellar and ISM galactic components can be recovered and if star formation history can be estimated from SED fitting using JWST NIRCam photometric + NIRSPec spectroscopic data.