If you're not young and in good health, can't you become a monk?

Anyone can receive a commandment (receive a commandment and become an official Buddhist) and receive a commandment name (Buddhist name). (While alive, of course.)
Furthermore, there may be temples that do Tokudo (become a small monk and have them register as a monk).
If it's just a ceremony and registration of documents.

However, realistically getting accepted by a temple is the same as getting a job.
That's because you'll be working as a temple staff member.
There are probably few companies that hire people who are neither young nor healthy.

Please ask about the precepts at the family temple or a nearby temple.
I think it's realistic to learn Buddhism as a lay believer at home while being taught by a temple or monk with a connection.
Also, I think it's quite possible to learn Buddhism at home.
You can also study by distance learning at Bukkyo University in Kyoto.

Why don't you talk to the temple of the family temple first?
There are big differences depending on the denomination, but in the case of the Jodo sect, there were people in their 50s and 60s when I received training at the dojo, so I think it would be possible if the dojo side even acknowledged that they couldn't sit properly.
However, before that, it is important to find someone to become a family temple or mentor, and to prepare well both mentally and physically.
It seems that some of the Buddha's disciples became apprentices at the age of 120, and from the Buddha's point of view, it seems that we are all affected by illness.
I hope learning Buddhism will lead to overcoming and reducing illness.
I hope you meet a good teacher.

In Japan, becoming a monk and becoming a monk is almost synonymous with inheriting a temple somewhere in the future.
And inheriting a temple means living while being exposed to things such as unique strong human relationships between monks, relationships with parishioners who are treated like VIPs when compared to stores (of course, there are monster crammers among those VIPs), moral harassment with higher hurdles than ordinary people, and discriminatory prejudice and slander against religion and boys.
It's not a comfortable place as people think. The reason why there are so many strange monks is also because they can be crushed by normal nerves. Sorry to sound threatening, but don't expect too much. Encounters between people depend on luck, but there is a good chance that your condition will worsen, and once you enter it, it is a world where it is extremely difficult to get out.

The reason why there are many monks who do not aim to become chief priests in the south is that it has been realized because family relatives and religious believers bear the full amount of financial support, such as initial expenses and living expenses, and support them. There is no such system in Japan.
After all, large temples have money but don't have time, and small temples have time but no money, so temples that have the conditions to take disciples other than successors are really limited. From there, it also involves whether the chief priest has that spirit, ability, and experience. If you do that, you'll be limited to less than 1% of the total.

Meanwhile, people living in the house stayed (removed due to character restrictions)

I recommend attending the Plum Blossom Course and the Reward Course. There are people who have actually improved their depression through the Plum Blossom Course.
In the first place, Mahayana Buddhism responds to excessive monasticism, “You can practice at home!” It is a group that argued and split up, and evolved along that line. Rather than relief from living as a monk, it is growing in the direction of how to stay at home and become familiar with Buddhism. Please hold on to that place. When a question about monasticism comes up on hasunoha, the answer “You can practice at home” is not the next best thing, but a sign that Japanese Buddhism is made that way.

appending
I thought I'd post a link to a temple I can think of, but on the condition that I'm 18 to 40 years old and able to do heavy work, etc., I added a word “it's not a sanatorium” at the end, so I'll refrain from doing it.
I recommend the plum blossom course over and over

I read it.

If it's just about becoming a monk, it doesn't matter if you're young or healthy. That's because it's just a ceremony called the Tokudo-shiki ceremony.
You can become a monk if you take the Tokudo ceremony and register as a monk.

However, when it comes to qualifying as a chief priest who is an official monk, it is quite difficult, and you can become a chief priest
Being a monk is such a difficult thing.

Basically, you have to graduate from college. Credit at Shomon University (Bukkyo University and Taisho University for the Jodo sect)
Also, people from other universities take training courses during summer vacation and get additional qualifications.

Then, he received permission, received the lineage of religious precepts, and successfully obtained the status of chief priest, and became an official monk,
You can get used to it.

The ascetic practice of the Jodo sect is so tough that you can't get into it before it's too hard, but you are seated
I'm a little worried because it seems like I can't do it.

Isn't it possible to do something about depression if the condition has subsided? I also developed depression in my 20s
I am there, but even so, I went to training, and after I left college, I also went to Motoyama.

However, if I were to practice training, I think it would be while I was young. I wonder if I'll be able to spend every day of that grueling ascetic practice from now on
When I say that, it feels impossible.