Do we get to submit our work in our common app ?

The Common App is the most popular application portal but it doesn't have the most flexible features. I would recommend that you look at the Coalition App which is a portal that covers about 150 top colleges. (schools like Rice, CalTech, Columbia, Yale, JHU, Duke, Emory, Harvard, NorthWestern, Olin, Princeton, RPI, Stanford, UNC, UChicago, UPenn, UMich, NotreDame, UT Austin, Vanderbilt, VTech, Wash U, Williams, Amherst, Harvey Mudd, CMC, Pomona, Swarthmore).

https://www.coalitionforcollegeaccess.org/

One major feature in the Coalition app is the LOCKER FEATURE. There you can upload various documents like .pdfs, movie or video files of your performances or work, and examples of your CODE.

You can either permission this just for colleges or also give access to your high school counselor or mentor or college consultant or parent to see as well.

This feature allows admissions officers to see much more of your work as part of your application. While 150 schools is not as many as the 900+ on the Common App, most of the Top 100 schools are on their partner list.

https://blog.collegevine.com/how-to-use-the-coalition-caas-locker-in-9th-through-11th-grade/

And if a school is not on the coalition app, go to the colleges website and see if they have a policy permitting you to use their own kind of locker software to make additional information submissions, for example SlideRoom by Liaison software. I know Princeton and Brown have these features.

Good luck.

Some universities support the submission of an optional portfolio; that seems to be the best way to share your web dev work. Check on the university website whether anything can be included in the portfolio, or whether they just allow artistic submissions. I would advise for submitting your websites in a portfolio if your university allows a non-artistic portfolio, and I would advise against submitting a portfolio if your university only allows artistic ones.