We will. The TESS (Transiting Exoplanet Survey Satellite) and the JWST (James Webb Space Telescope) will be launching in a few years. The two will sort of act a

We will. The TESS (Transiting Exoplanet Survey Satellite) and the JWST (James Webb Space Telescope) will be launching in a few years. The two will sort of act as a spotter-sniper pair -- TESS detecting planets and JWST zooming in. Both are far more powerful than their predecessors, Kepler and Hubble. There is also plans (not yet funded) to use "starshade" occulter to directly observe planets that don't pass in front of the parent star (by blocking the starlight). My personal estimate is that we'll definitely detect oxygen in a planetary spectrum within the next 10 years. Which will mostly likely mean photosynthesis on the surface.