Add Values Across Multiple Sheets

Hello Excel Geniuses,

I am building a workbook where worksheets will be added over time. Each worksheet will be in the same format and the values I need will be in the same cells. I would like to automatically sum certain values, based on the name of a specific cell in each worksheet and update the master sheet every time a worksheet is added. I would love to do it with a formula if possible, but am open to an "Update" button. I have attached a sample workbook to explain better. Thank you in advance for all your help!!!!

Thank you for your help! This seems to work ok. I thought I would be able to adapt the answer to what im really trying to do, but since i'm more familiar with formulas than VBA, Im now asking to take a look at the attached file which more accurately represents my final goal. If a formula is possible that would be amazing, but if you work it out with VBA in this format, I think i can adapt it. Thanks so much for your time!