Want to switch to accrual method

As title suggests, the issue is that I need some insight on how I can get this properly to work.

Normally I did not keep track of beginning or end inventory so I am going to just count whatever I have today and considered it my beginning inventory to start off the year properly.

My question is under accrual method in quickbooks Ive noticed the second you send a invoice for example if a customer get an invoice for $100k it automatically starts to add to my net profit. The issue is that sometimes it takes customers a month to pay it. I do not send products until its fully paid therefore I still have all risk until then.

Now lets say end of year comes in and my net profit is at 100k then i open a invoice for 100k now my net profit is 200k ? I do not want to pay taxes on things i have not even sent out yet. Is what I am saying true if so how can I fix this?

Basically I am going to keep track of inventory at beginning of year and end of year thats about it, i do not plan to do it quarterly, as I can estimate my taxes from the year before and this is just easier for me.

I want to switch to accrual method but also need to be realistic on earning profit because if i have to pay taxes on $200k even if my customer did not yet send money or better yet decided to cancel invoice then I would probably have to wait until next year to get my refund back.