How to reset hard-drive partitions into original state?

Hey, i have created a bunch of partitions with my hdd but now i want to combine them all into one so i can have it in factory settings. i was thinking about doing a fresh install and wipe of all data so losing any data is not a problem. Is there any boot tool or something like that which can help me fix it?

Ignore the D drive because that is a secondary hdd. i also have some unallocated space which i cannot combine with my c drive or anything. i have tried some tools which i downloaded or used the windows built in ones but it dont work. Any advice?

During OS install you will be able to delete the partitions, giving you the entirety of your hard drive as unallocated space.  You can then create a single partition and install your OS to that.

OK, but will it let me combine partitions and shet?

Just delete them all, then make a single big one.