As you read through you articles for te critical appraisal portion of your review, pay attention to the type of data in each study. You may also want to look at other systematic reviews published on similar topics to see what type of data they compared. Always error on the side of collecting too much data rather than not enough.
You will need to create your own form based on your own data needs, but you can follow the general format found in these templates:
Cochrane Data Extraction Template
Section 1.3.3.2 in York University's Undertaking the Review
You can run meta-analyses through software packages like the Metafor Package. The package consists of a collection of functions that allow the user to calculate various effect size or outcome measures, fit fixed-, random-, and mixed-effects models to such data, carry out moderator and meta-regression analysis and create various types of meta-analytical plots.
Once you have all of the data points needed for a Forest plot, wight, Odds Ratio, Lower Confidence, Upper Confidence, and Patient Population. You can use a Forest Plot generator from Evidence Partners to create the actual plot.