The Almighty appears and bestows His Shekhina upon the world to the extent to which human beings call to Him. In other words, the Shekhina resides in the space that human beings make for it. Regarding prayer, this means that the Almighty is revealed to the same degree to which people call out to Him...
The shliach tzibur who leads the Selichot service does not ask God to appear, but rather actually substantiates the Shekhinah - and this power is a divine one...In a standard prayer service, the person stands on one side, opposite the Almighty. During Selichot, by contrast, we stand not opposite the Shekhina, but rather amidst the Shekhina; we are surrounded by it and bring about its manifestation. God Himself is situated at the head of the congregation forming the chariot. He does not listen to this prayer service, but rather is present within it.
https://etzion.org.il/en/holidays/studies-repentance/understanding-13-middot-introduction
A person should try to pray in the synagogue with a congregation, and if they are unable (lit. "anus", coerced) to come, they should intend to pray while the congregation is praying [This applies to people living in small setttlements, unable to pray in a minyan -- they nevertheless, should pray shaharit and arbit during the time of congregational prayer -Sma"g] If they (the person) could not pray at the time when the community pray, and is praying alone, nevertheless they should pray alone in the synagogue.
(ד) . . . . ולמה נקרא שמו מקום אלא בכל מקום שהצדיקים שם הוא נמצא עמהם שנאמר בכל המקום אשר אזכיר את שמי.
(4) .... Why is the name of the Holy One, blessed be God, called Maḳom (place)? Because in every place where the righteous are, God is found with them there, as it is said, "In every place (Maḳom) where I record my name I will come to you, and bless you" (Ex. 20:21).
Rabbi Meir was wont to say the following idiom: Study with all your heart and with all your soul to know My ways and to be diligent at the doors of My Torah. Keep My Torah in your heart, and fear of Me should be before your eyes. Guard your mouth from all transgression, and purify and sanctify yourself from all fault and iniquity. And if you do so, I, God, will be with you everywhere.
(ב) . רַבִּי חנניא בֶּן תְּרַדְיוֹן אוֹמֵר...
שְׁנַיִם שֶׁיּוֹשְׁבִין וְיֵשׁ בֵּינֵיהֶם דִּבְרֵי תוֹרָה, שְׁכִינָה שְׁרוּיָה בֵינֵיהֶם, שֶׁנֶּאֱמַר (מלאכי ג, טז), "אָז נִדְבְּרוּ יִרְאֵי יהוה אִישׁ אֶל רֵעֵהוּ וַיַּקִשֵׁב יהוה וַיִּשְׁמָע וַיִּכָּתֵב סֵפֶר זִכָּרוֹן לְפָנָיו, לְיִרְאֵי יהוה וּלְחֹשְׁבֵי שְׁמוֹ.
(2) Rabbi Chananya ben Teradyon says: ...Two who are sitting together and there are words of Torah [spoken] between them, the shekhinah rests with them, as it is said (Malachi 3:16): “Then those who feared the Lord spoke one with another, and the Lord hearkened and heard, and a book of remembrance was written before Him, for those who feared the Lord and for those who thought upon His Name.”
What is the meaning of that which is written: “But as for me, let my prayer be unto You, Lord, in a time of favour; O God, in the abundance of Your mercy, answer me with the truth of Your salvation” (Psalms 69:14)? When is a time of favor? It is at the time when the congregation is praying.