You’re smart to take a long term approach to your training. We see all the time people who stick with a training plan amazed by what the can accomplish 1 -2 years on. Each time you repeat a long training cycle you will come out the other end at a much higher level that’ve been at before. But since this all new to you and you want to make the most of the summer season I think you might be well served by the 5 week alpinism plan that Steve has laid out. Yes, it is short and will not give optimal results. But it will will introduce you to structured training and it will give you a boost in fitness that you’ll notice. It will also save you the time and effort of creating your own plan from scratch. If you like the results then the next cycle you can go longer and see even bigger gains.
Even better would be to proceed that 5 week structured plan with your own transition period of 6-8 weeks where you emphasized general strength/core and basic aerobic capacity. This will give you a change to learn some new things and practice some new skill about training and yourself.
This fitness base we harp on in the books and the site is a long term proposition and there is no quick fix but the above suggestion will whet your appetite for more I’l pretty sure.