Without a workng Home button, whenever that iPad runs into issues, you are always going to run into a roadblock.
To do an easy, simple hard reset of an iPad, ALL external, physical buttons need to functioning as they should.
Without a functioning Home button you cannot perform a simple hard reset of that iPad.
A non-functioning Home button is always going to be problematic any time something unexpected happens to that iPad.
I am afraid you will either need to repair this iPad to get that Home button working again OR purchase another iPad that DOES have a perfectly working Home button.
You really need to seriously consider replacing that iPad with a purchase of a new iPad model OR a much, MUCH “newer” and less expensive, refurbished or used iPad models, from better known, trusted sources, like other Apple product/device retailers/resellers, some locally or from online, on the Web/Internet, capable of running the latest iPadOS versions.
There are PLENTY of newer, older iPad models that can run the latest, current versions of iPadOS.
If you need OR ONLY able to purchase older, less expensive iPad models, look at older IPads from 2014 and later.
All of these older model iPads below CAN run the latest iPadOS versions and the up and coming iPadOS 15.
2014, 9,7 inch screen iPad Air 2 models
2015, 7.9 inch screen iPad Mini 4 models
2015-2017, 12.9 inch screen iPad Pro models. ( 1st gen Pencil support )
2016, 9.7 inch screen iPad Pro models ( 1st gen Pencil support )
2017, 10.5 inch screen iPad Pro models ( 1st gen Pencil support )
2017, 9.7 inch screen iPad 5th gen models
2018, 9.7 inch screen iPad 6th gen models ( 1st gen Pencil support )
2019, 10.2 inch screen iPad 7th gen models ( 1st gen Pencil support )
2020, 10.2 inch screen iPad 8th gen models. ( 1st gen Pencil support )
Get the largest internal data storage model you can afford as NO Apple iOS device has expandable storage.
I am sorry that you had to learn all of this, but this does not change any of the facts regarding the issues with your current iPad.
Sorry & Best of Luck to You!