What are examples of spores on sporangium (like what plant and such would i find them) that i can physically find?

Hi! Spores are produced by sporophyte, or the spore bearing generation. Spores can be found in non seed bearing plants; like liverworts, hornworts, mosses and ferns. In ferns, you could physically find spores on the underside of the frond. These sporangia may clump together as well, to form sori. I hope this helps, let me know if you have more questions!

B.) nitrogen fixationnitrogen fixation is the process of nitrogen molecules seeping into the soil and inside plant roots and bacteria. it gives more "life" to plants

Ican not answer this question since it does not have enough information