How to add/merge two layers into one by not loosing first layer attributes?

[GIS_Rookie]

Hello everyone,

I'm out of ideas, so I need help. 

Is there some tool to merge two layers together but not loose first layer attributes? Well, the goal is to add geometry (yellow) to layer (green). 

For example picture - Yellow geometry needs to be added to green. Those two layers. Okay, with merge, but then I will loose attributes. What else without merge tool I can try? At the moment using ArcGIS PRO 2.9.2.

Thanks for the help. Have a nice day 🙃

[Luke_Pinner · Accepted solution]

Use the Merge tool and use the Field Map parameter.