yps777,
I want to use 50 or less of the previous soil and 50 gravel
Don't use any of the old soil. Have you heard the saying that a chain is only as strong as its weakest link? Well your medium will behave the same way, the finer particles will sift in between the larger particles and effectively your mix won't be much better than it is now. The best draining medium is composed of particles of approximately the same size. I don't use anything that resembles the medium in your pots. I use Pine bark or Pine bark mulch in a size that is similar to my inorganic components.
(one layer of soil one layer of gravel)or soil mixed with gravel and a layer of gravel.
Another important concept is that your medium should be uniform throughout, not stratified or layered as you suggest. The idea of using a coarse drainage layer has been discredited. Size your components to a uniform dimension removing the large and the small particles and mix them until a consistent product is achieved.
I don't have any other materials
Yes, this seems to be where a lot of new growers fall short. Sometimes it is difficult to locate appropriate ingredients. Some growers here use chicken grit, not the kind made from Oyster shells though. The first year I got wise to this system I smashed up some red bricks, the old kind that are soft and break easily. It was no fun and the next year I made sure I purchased some better materials.
You can also crush lava rock, the kind some people use for landscaping purposes. Grit from a river or creek can be used but it is kind of late in the year to go mucking about in the water. But you only need a few Quarts/Liters. If you try to make you own, a screen with opening of about 1/8 inch (or perhaps 4 MM) is almost a necessity.
Of course bonsai soil can be purchased online but it may take longer to reach you than you would like. Not to mention shipping costs will likely be a concern. I cannot offer any sources in you area.
Don't rush into anything, better to leave it for now than to make another poor choice. I feel that I have to ask again, have you begun to do your research/homework? I get the feeling you have not.
https://www.helpfulgardener.com/forum/viewtopic.php?t=3422
https://www.bonsai4me.com/Basics/Basics_Soils.html
https://www.bonsailearningcenter.com/Tips&Advice/soil.htm
https://www.evergreengardenworks.com/soils.htm
Norm
and I watered it.
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.one thing solved next on list is inorganic soil for Elm and Pepper(I will change the soil in the summer 