Why re-invent the wheel; or hunt for a dedicated application unless it's necessary. Spreadsheets and Presentation programs have been around for a long time. A little web-searching using a target phrase such as "excel template project management free" may turn up just what you need, Perhaps from the following links:
https://www.hubspot.com/business-templa ... ment/excel
https://www.projectmanager.com/blog/8-m ... -templates
https://www.smartsheet.com/top-project- ... t-template
https://www.tacticalprojectmanagement.c ... -managers/
Well, some of the above aren't absolutely free. They're distributed as advertising with the first few rows serving that purpose. Kind of like the junk mail my wife and I flip on their backs, write up TO Do lists and place on the refrigerator so that only one of us --whoever takes the list-- rather than neither or both of us will pick up, say, bananas.
At least with the templates I played with, they don't like having their ads removed. But they don't seem to mind having their useful rows and columns copied to a NEW Spreadsheet.
Of course, if I were more ambitious, I'd rebuilt them from scratch. After all, they're only rows and columns with text or formulas; maybe some coloring to spice them up. The templates can be used for reference and provide the formulas.
Other resources found by musher0, https://1stwebdesigner.com/online-proje ... ent-tools/