Hi there I am Arya , gsoc aspirant pursuing Btech. in computer science

[arya]

I am interested in project Replacement of deprecated Gtk classes @rodolforg do you any suggestion for me

[rodolforg]

Hello @arya. Welcome.

First of all, read these guidelines:

Google summer of code student guidelines

Hey there, you’re here means you are interested in participating with us(Synfig-studio) in GSoC 2020 that’s awesome. I’ll recommend you read the following so you already know most of the things Please introduce yourself on forum first here ->Google Summer of Code 2020 and let us know about you, which idea you will be willing to work with. Ask for anything regarding the project on forum. Most of the information is already there however you can also ask your silly doubt over here …

After that, you could try some of Good First Issues to be used to Synfig code, community
and workflow.

Regarding the project idea itself, take a look at files related to menu actions (like synfig-studio/src/gui/app.cpp).